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These examples address all of the elements on figure 1 from the article (above left), showing the components that research has shown to be important for effective instruction, along with important components of effective implementation in the classroom such as tasks with clear deliverables and enhanced through social learning. The degree to which particular elements are explicitly addressed varies with example. Although it varies with example, many of these activities involve a class orchestration as shown in the figure above right. While most instructors can see how to do this in a class of 20 or 30 students, they have more trouble with how to do it in classes of 100-300. In these examples, we have links to videos showing two examples of how this is done. There are many other examples of good instructional activities, these were simply ones covering a range of topics and levels that were readily available.

List of examples:

Physics

1. Day – data characterization in introductory lab class (histogram and standard deviation)
2. Holmes – quantitative critical thinking in introductory laboratory class
3. Jones – upper level physics majors’ course
4. Lepage – graduate quantum field theory
5. Rieger – introductory physics (mechanics) large lecture theatre ( showing use of worksheets and group work in this setting)
6. Wieman – introductory quantum mechanics 25-50 students

Biology

(All of these come from peer-reviewed published articles. The journal “Course Source” is specifically devoted to publishing peer-reviewed instructional examples in biology, providing a unique resource for post-secondary biology instructors.)

7. Smith – introductory genetics, large lecture class using clickers
8. Stowell and Martin – advanced ecology and evolution course, evolution and management; trout case study, using worksheets
9. Pelletreau – central dogma, large lecture intro bio class, using clicker questions

Earth Sciences

10. Scoates – introduction to mineralogy synthesis activity in large lecture theatre ( showing and explaining this activity).

Mathematics

11. Code – introductory calculus, discontinuous functions

Statistics

12. Roll – framing instruction in statistics for novices

General

13. Barker – two stage active review and knowledge organization of course material

The following links on the CWSEI website also have a variety of guides on details of design and implementation of research-based instruction.

• Course Transformation: a collection of documents offering detailed advice for departments and faculty members on how to redesign courses.
• Instructor Guidance: a collection of short guides for instructors – on assessment, clicker use, student engagement, etc., etc. – that illustrates in concrete terms the pedagogical philosophy (active engagement of students) underlying these initiatives. The advice is highly practical.
• SEI Videos: a collection of videos that show, among other things, what active learning looks like.
• Resources: an annotated bibliography of papers on the research behind many aspects of active learning.

James Day, Dept. of Physics, University of British Columbia

Brief summary of the level and subject of the course in which the activity is used

The lab was an independent part of the first semester of an introductory calculus-based physics course intended for students planning to take higher level courses in physics and astronomy. The activity was used in multiple sections, of about 25 students each.

Principles and practices the activity addresses

This activity addresses all of the practices and principles in Figure 1; it is, after all, a carefully constructed invention activity. I am happy to defend this assertion if it doesn’t seem obvious but will skip it for now, for the sake of brevity.

Why I felt it was successful

Subsequent transfer measures demonstrated that students are learning, retaining, and re-applying this knowledge. In initial testing, only 55% of students identified all three key features of some given distributions but none of them calculated a standard deviation. Some weeks after this activity, when presented with an opportunity to “quantify their data” (beta ray emission from a Sr-90 source), with no additional instruction, essentially all of the students calculated the standard deviation. The same was true of when and how to create histograms. It was clear that the students learned not only to create histograms and calculate standard deviations, but they had also developed the much deeper understanding associated with recognizing the underlying purpose of these techniques and when it is suitable to use them.

How the activity was implemented in the course, including what were the student deliverables

Self-created pairs of students were given the activity (see associated .pdf attachment). They were then given about 30 minutes to work with the data: building a graphical representation of the data and creating a “blue-ribbon formula” to quantify the data were the deliverables. After 30 minutes (into parts 1 and 2, respectively), the instructor interrupted with a short lecture on how the expert would tend to quantify this data: build a histogram and calculate the standard deviation.

See the teaching activity here

Natasha G. Holmes, Ann S. Bowers Assistant Professor, Department of Physics, Cornell University

First-year physics lab course – extensively tested in calculus-based courses at a broad range of institutions (from Community College to Ivy League)

Which of the principles and practices on fig 1, the activity addresses

• Disciplinary expertise
• Prior knowledge & experience
• Motivation

Why you felt it was successful

Meets students where they’re at, presents conflict with their expectations and prior experiences to re-orient them the nature of science and measurement to be used in the lab course, provide extensive scaffolding to support them in productive engagement while also facilitating student agency and ownership. Extensive data (published) showing students’ adoption of better experimental practices and quantitative critical thinking. See Holmes & Bonn (2015), The Physics Teacher.

How the activity was implemented in the course, including what were the student deliverables

The activity spans two two-hour lab sessions. The students work in groups of 2-3 through the lab instructions with extensive support from in-class instructors. Each week, the students submit lab notes that summarize their methods and thinking throughout the lab.

See activity here.

David J. Jones and Kirk W. Madison, Department of Physics and Astronomy, University of British Columbia

Carl E. Wieman, Department of Physics and Graduate School of Education, Stanford University

This is a study of active learning pedagogies in an upper-division (fourth-year) physics course. This work was guided by the principle of deliberate practice for the development of expertise, and this principle was used in the design of the materials and the orchestration of the classroom activities of the students. We present our process for efficiently converting a traditional lecture course based on instructor notes into activities for such a course with active learning methods, and the details of implementation in the classroom. The work is discussed in detail in the open source .

Each activity was motivated either verbally by the instructor or in the written preamble.

• Mathematical models were tied to phenomena, and “real-life” examples were employed.
• Prior course material was included wherever possible to maximize continuity.
• Questions were ordered from least to most difficult to optimize engagement.
• Activities were designed so that continuous work did not exceed 15 min and at least two class feedback sessions led by the instructor could occur over the full class period.
• Activities included some work that was judged to be just beyond what the students were capable of, so as to optimally prepare them for the feedback period.
• Long or elaborate algebraic manipulations in activities were minimized so students could focus on underlying physical phenomena.
• “Bonus” questions were included to challenge the most advanced students. Below we give three examples of the worksheet activities used in class (appendix a. from above article).

The students were very engaged with the material and on common exam problems showed a 15% improvement over traditional lecture instruction, with an effect size greater than 1 after the transformation. Because the material tested was so mathematically advanced and broad (including linear algebra, Fourier transforms, partial differential equations, and vector calculus), we expect the transformation process could be applied to most upper-division physics. 

See worksheet here. 

Contrasting Cases worksheet activity

Clicker question (multiple choice) on field symmetries

G. P. Lepage, Cornell University

The Course

Introduction to relativistic quantum field theory for second-year graduate students and advanced first-year students. The course was taught in an active-learning format throughout. Students were assigned reading (in the text or research articles) for each class, and completed a pre-class “quiz” online that probed their understanding of the reading (graded for participation). Classes involved a mixture of group work on worksheets (handed out at the beginning, collected at the end, and graded for participation) and lecture, mostly in response to the group work. The lecturer circulated around the class (20 students) during the group work, answering questions and helping groups get unstuck, as needed. The online quiz was frequently used to provide the set up for worksheet problems in the subsequent class. Regular (and extensive) homework was assigned and graded for correctness. There was a take-home final at the end. Everything was “open-book”.

The Question

One of the early triumphs of relativistic quantum mechanics was its prediction of the existence of anti-particles. Consider the following types of (non-interacting) quantum field theory:

The second and fourth theories require new anti-particles, distinct from the original particles. The others do not. What is the rule that determines whether you need new anti-particles?

The Rationale

This problem comes very early in the course. The text book begins with a discussion of the quantization of a real-valued scalar field theory (first case). It then generalizes the discussion to allow for a complex-valued scalar field (second case), discovering the need for a new particle, the anti-particle, in the process.

This is an example of using contrasting cases to help students understand what is going on. Given only the first two cases, one might conclude that the general rule is that complex-valued fields have new anti-particles. That idea is undermined, however, by the third example, which has a complex field but no anti-particle. Maybe the third case is special because its field equation is linear in ∂t, unlike the first two which are quadratic. The fourth case, however, also has a field equation that is linear in ∂t and a complex field, but also a new anti-particle.

In fact, the rule has two parts. First one must determine whether the field equation has negative energy solutions — that is, solutions whose time dependence goes like e-iEt with negative values for E. In such cases the Fourier decomposition of the field must have two terms, one for the positive-energy solutions e-ipx and one for the negative-energy solutions eipx (the students know that ���≡Ept-px where Ep is the energy associate with 3-momentum p). Anti-particles are associated with negative-energy solutions. The third case is the only one that is lacking negative-energy solutions: it requires Ep=p2/2m, which is positive, while the other equations all imply that Ep2=p2+m2, which has both positive and negative solutions. The last case, like the third case, is linear in Ep, so one might worry that it has only one solution as well, but it is a matrix equation whose solution leads immediately to Ep2=p2+m2 (Dirac’s goal in designing it).

Relativistic theories typically have both positive and negative-energy solutions, and so need two terms in the Fourier expansion. For the real scalar field the coefficient of the negative-energy solution must be the conjugate of the coefficient of the positive-energy solution (so that the field is real-valued). This is an example where a particle is its own anti-particle; there is no additional particle. The complex field contains twice as much information, because it has a real and imaginary part, and so needs twice as many Fourier coefficients: ap and bp†, where the first is associated with the original particle, and the second with the new anti-particle.

In summary, students need to both determine whether there are negative energy solutions, and, if so, determine whether the number of degrees of freedom encoded in the field requires independent Fourier coefficients for the positive and negative-energy terms. In practice, many students managed to understand the relevance of the number of degrees of freedom, but few paid attention to the need for negative-energy states, despite this being the starting point for many elementary discussions of anti-particles — prior knowledge that needs to be activated for use here.

The contrasting cases were carefully selected to make it difficult for students to fasten on a simpler rule by thinking too narrowly about the possibilities. Each of the surface features mentioned above — complex versus real, first-order versus second-order, scalar versus matrix — is relevant to the correct rule, but none is definitive on its own. A major point of the exercise is to get students to think through how these surface features relate to the real issues.

The mathematical manipulations involved in this problem are trivial for physics students at this level. By this point in the course, everyone has worked with each of the first three field theories. The Dirac theory comes later in the course, but almost everyone in the class has some familiarity with it from previous courses. Another example that could have been included is the Majorana spinor field, which is a relativistic theory with a complex field and a first-order field equation, but no new anti-particle. Students were given an opportunity to revisit the thinking used in the present problem when they were analyzing Majorana fields for a homework problem several weeks later.

The mathematical manipulations involved in this problem are trivial for physics students at this level. By this point in the course, everyone has worked with each of the first three field theories. The Dirac theory comes later in the course, but almost everyone in the class has some familiarity with it from previous courses. There are other examples that could have been included such as the electromagnetic field. The most interesting case that perhaps should have been included is the Majorana spinor field, which is a relativistic theory with a complex field and a first-order field equation, but no new anti-particle. Students were given an opportunity to revisit the thinking used in the present problem when they were analyzing Majorana fields for a homework problem several weeks later.

Georg Rieger, Physics & Astronomy, University of British Columbia

The examples below are used in two calculus-based introductory physics courses. Q1 is from an introductory Mechanics course, typically taken by STEM students in term 1 of their first year. Q2 and Q3 are from an introductory course in Electricity and Magnetism, also taken by STEM students in their first year (term 2).

The questions were in part inspired by chapter C in Schwartz, Tsang & Blair “The ABCs of how we learn” and the implementation of contrasting cases for teaching Faraday’s law (Kuo and Wieman, 2016). In general, contrasting cases are great for small group discussions and for enhancing conceptual understanding. I am using increasingly more contrasting cases in my classroom activities. The questions I have selected don’t involve solving mathematical equations, which tends to inhibit discussion. Here students are asked to analyze graphs and a circuit diagram and make connections to other representations. The tasks are therefore relatively difficult, which is another ingredient for lively discussions.

All three activities fall into the ‘Learning through practice with feedback’ category: students are asked to complete specific tasks and come up with correct solutions. All three tasks involve combining prior conceptual knowledge and are therefore relatively difficult, which is excellent for small-group discussions. The correct way of reasoning in all three cases requires disciplinary expertise. In discussions, students apply their understanding of the questions, remind each other of concepts and procedures and try to combine these to find a solution. The solutions may not be completely correct, but often contain correct elements the instructor can build on in discussions with groups or in the follow up discussion. Here the instructor highlights expert reasoning that can involve repetition/clarification of the underlying concepts, question interpretation, use of information, and procedural knowledge. All three tasks are meant to develop a richer and deeper understanding of the underlying concepts:

• Potential energy and conservative forces (Q1)
• Time constants and exponential laws in RC circuits (Q2)
• Parallel and series connections in combination circuits (Q3)

Each activity takes around 10 - 15 minutes.

Q1

This is an end-of-chapter textbook question (P11.40 from: Knight’s “Physics for Scientists and Engineers, 3^rd edition). In my view, this task is much better as a small-group activity in class, rather than a homework question done alone at home. Drawing questions are great for getting whiteboards involved. In students discuss and modify their graphs until they reach consensus. They often exchange ideas with other groups, instructors or teaching assistants. After coming to a consensus students copy the solution to their worksheets, which they keep for later studying.

The question is about connecting a conservative force (such as the force of gravity) to the corresponding change in (gravitational) potential energy. The information is given in graphs and students first have to connect the underlying calculus equations to the graphs. The pre-class reading assignment has introduced students to the relevant concepts and this is now practiced. The same curve is used for both cases to emphasize careful interpretation of graphs and paying attention to information on the axes. First students have to decide which graphical interpretation (area vs. slope) should be used in each case. In case (a) the change in potential energy can be obtained from the force by integrating, which is the ‘area under the curve’. The students have to pay attention to how much the area is changing from one position to the next. They have to decide that it is best to divide the curve into smaller intervals and consider how much each interval is adding to the total. Then, they have to appreciate that the amount each interval adds is first increasing up to the maximum force at 0.5 m and then a decreasing, but still adding to the total. In addition, they need to remember a negative sign in the integral equation and that they should use the negative area under the curve. Last step is for students to put numbers on the axes of their graphs and realize that they can use the total area as calibration. From my observations, successful groups proceed in this order, i.e. they first come up with a curve that looks like a stretched-out “S” and then realize that they should take the negative mirror. Part (b) is a bit easier since the force can be obtained from the potential energy by taking the derivative, which is the slope in the U vs t curve. There is again a negative sign in the corresponding equation, so they have to use the negative slope. Students should divide the curve into two portions, since the slope is changing sign at 0.5 m. Finally, the students have to look at the axis to obtain numerical values for the two slopes.

The resulting graphs look very different from the given ones and cannot be obtained by guessing. After giving students sufficient time, the instructor follows up by drawing the solution on a board or a document camera while providing detailed explanations.

Q2

on the next page is about the behaviour of RC circuits. This is a worksheet task that is also best done in small groups. It asks students to think about the time behaviour of RC circuits governed by the time constant t = RC. It connects this concept to two representations: an exponential growth equation (discussed before) that describes charging the capacitor and the corresponding graphical representation in a plot. In this example, students need to consider possible changes in charging time, in maximum charge, and in maximum current. I use this task at the end of my discussion of RC circuits allowing me a review and final discussion of RC circuits, time constants and the exponential law.

In case (a), the students have to consider the effects of doubling the capacitance. Almost all students understand that charging the capacitor now takes ‘longer’ since the time constant doubles. To draw the new curve, they first they have to pay attention to the x-axis to realize that it is labeled in terms of the time constant t. Next they have to interpret the numbers on the y-axis and understand that it is explicitly labeled in terms of Q = C e. The charge is thus expressed in terms of the capacitance and the maximum voltage. Now students need to consider whether or not the maximum charge has changed (it has). Finally students should generate a few useful data points to draw the new curve. For example, the data point corresponding to (0.632 C e , t) is obtained at (1.264 C e , 2 t). The charge vs time curve is thus stretched out by a factor of 2 in both dimensions. The corresponding current curve is only stretched in out in time. Students only have to realize that the maximum current does not change, but that it takes twice as long for the current to decay. Again students should generate two or three useful data points. For example, the data point corresponding to (0.368 I₀, t) is obtained at (0.368 I₀, 2 t).

Similar consideration go into case (b) in which the resistor is doubled. Again students need to find that it takes twice as long for the capacitor to charge, but that the maximum charge is not affected. So the charge curve is just stretched in the time dimension by a factor of 2. Lastly, for the current curve, students have to decide whether time, current or both dimensions are affected by doubling the resistance. The labels on the current axis provides the necessary hint, as the maximum current is expressed by the emf and the resistance. Students thus have to realize that this leads to half the maximum current, so the curve looks fairly ‘flat’. One data point is necessary to see this: the data point corresponding to (0.368 I₀, t) is obtained at (0.184 I₀, 2 t).

I have used the deceptively easy looking “Q3” many times in class as a clicker question and occasionally on exams. The question challenges students’ understanding of circuits on a deep level.

• They have to interpret the question and understand that they should compare the behaviour of two circuits: one with three bulbs, as shown, and one with just two bulbs (a and b). Q3 can thus also be viewed as a contrasting case.
• Students have to know that light bulbs behave like resistors in a circuit.
• Students first must realize that all current from the battery goes through bulb a, but this current may not be the same in the two cases.
• Students should then decide to consider the overall (or ‘equivalent’) resistance in the two circuits and find out if the current from the battery is either larger, smaller or the same.
• To compare the equivalent resistance, students have to decide which bulbs are in series and which ones are in parallel. Then they have to apply the rules for resistors in parallel and in series.

Students have to deal with a combination of parallel and series connections. Many students mistakenly think that bulbs a and b are in series and bulb c is just an extra bulb, so when it is gone there is less resistance in the circuit. In reality, bulb a is in series with the parallel combination of bulbs b and c, which has less resistance than bulb b alone.

In class, this question is best used in “classical” peer instruction mode: give students a bit of time and ask them to answer individually first (without discussion) before giving them time to discuss it with their neighbors and ask them to come to a consensus. This is followed by a re-vote and a class discussion of the solution. I use this question after I have discussed basic series circuits and parallel circuits and when I go into more difficult combination circuits. I emphasize to the students that they should be on the lookout for junctions that mark the beginning of a parallel circuit.

Carl Wieman, Dept. of Physics, Stanford University

Brief summary of the level and subject of the course in which the activity is used

This is for an introduction to quantum mechanics course, taken early in their second year by prospective physics majors and some engineering majors who have desire or requirement to learn QM. The activity was used in classes that varied between 25 and 100 students. This course presents quantum mechanics in terms of formulating predictive models based on experimental observations, and as those models are further tested against experiment, the evolutionary development and use of improved models. This avoids the problem of quantum mechanics being seen as just a proclamation of utterly non-intuitive and incomprehensible claims and equations.

Principles and practices the activity addresses

This activity addresses all of the practices and principles in Figure 1. It involves practice in expert representation of data both graphically and mathematically, followed by interpretation. It carefully builds on prior material, relates to experimental observations they have been shown, puts the material in a context that they can be more engaged in and see how applies, thus is motivational, uses online simulations to reduce the cognitive load in presentation of material, and uses well defined tasks that each student must complete in discussion with peers, and for which there is ongoing immediate feedback and guidance from the instructor. 

Why I felt it was successful

First, the students were extremely engaged—they would almost never leave at the end of class. Instead they would continue working and discussing until the subsequent class kicked them out of the room 15 minutes later. Second, we carried out multiple measures of their mastery of these concepts and they students score very high, considerably higher than students taught by lecture format.  are published in Phys. Rev. PER. Finally, we measure their attitudes about quantum mechanics. They are more likely to see QM as something that is comprehensible and that they can understand than students taught traditionally.

How the activity was implemented in the course, including what were the student deliverables

Students worked in self-organized groups of 3-4 completing the worksheets, with each student having to complete and turn in copy of their individual worksheet. As they worked through the activity, the instructor circulates, monitoring progress and answering question, and every 10-15 minutes pulls the class together to go over progress, questions, and answers up to that point. 

The teaching activity itself

Below are two worksheets. One on the photoelectric effect that requires one class, and one on quantum superposition and atomic transitions that has two parts that goes over two classes.

Name (print) __________________ (work in groups but complete worksheets individually)

Photoelectric effect worksheet

Describe dependence of electron emission as function of:

1. Frequency of light
2. Intensity of light (don’t get too hung up on intensity dependence near frequency threshold—subtleties. Imagine shaking a swimming pool with foam.)
3. Time delay between light turn-on and electrons first produced. 
4. Dependence of the current on small positive and small negative battery voltages.
5. What changes in photoelectric signals when the type of metal is changed?
   1. Describe what happens, be quantitative. Use graphs & eq. as useful.
   2. Say what classical model would predict. What matches? What is different?

(distinguish between observations and inferences)

Name____________________________(work in groups but complete worksheets individually)

Quantum superposition and atomic transitions

Time dependence of wave functions and probability distributions. Optical transitions. (Likely requires two class periods to complete, part I and part ii. Is LOTS of in class discussion.)

Go to phet bound state sim. Set the potential to be harmonic (a bowl). This is a closer approximation to a real atom than a square well, as it has spatial dependence and symmetry properties more like a real atom, which matters for this worksheet. 1d or 3d Coulomb would be even more realistic, except the sim only shows states of L=0, which hides lots of the important physics involved in the superpositions of energy states. 

Part 1. Superpositions and time dependence.

1. What is shape and time dependence of first three lowest energy wave functions in the well?
2. 1. What is shape and time dependence of the probability densities for the three lowest energy states?
   2. Write down the mathematical description of these states (leaving the spatial dependence as unspecified functions, Ψ₁(x), Ψ₂(x), etc.) including the time dependence. Show how the mathematical description agrees with your observations above.
3. Click on “superposition state” in the sim. Create a superposition that has 1.0 x wave function for level #1 + 1.0 x w.f. for #2 and try running. Why does sim tell you that is unacceptable as a wave function?
4. 1. Normalize the wave function into equal amounts of #1 and #2. (a “superposition” state) What is the shape and time dependence of the wave function and the probability density of an electron that is in this superposition state?
   2. As you did in 2.b, describe this mathematically and evaluate the time dependence. Show how it matches what you described in 4.a.
5. Try a few other superposition states. What can you conclude about what is needed to create a wave function that describes an electron that moves through space, as an example of time dependence?

Part 2. Emitting and absorbing light in atoms, and figuring out transition preferences for electron going between energy levels in an atom (similar to this case of levels in harmonic potential). 

Classically, to produce light you need an oscillating electric charge, preferably an electron, with the frequency of oscillation matching the frequency of the light. The distance it oscillates back and forth, r, times the charge q, is the “dipole moment” and qr characterizes how strongly it will emit light. Also, if a charge is initially stationary and you shine light on it, it will start oscillating and in the process absorb light, and the strength of the absorption is also characterized by the dipole moment qr. Here you are going to investigate how dipole moments can arise quantum mechanically in a system in which you have electrons bound in a potential, such as an atom or a harmonic oscillator, and what determines the relative strengths of the dipole moment under different conditions.

6. Consider the superposition state you made in 4. Compare that with a superposition of equal amounts of #1 and #3. Which, if either, of these, would correspond to an electric charge moving back and forth, and hence would produce light? How would the frequency of the light be related to the energy levels of the electron in the two cases? 
7. 1. If the electron was in level #1 and you sent equal amounts of light on it at frequencies corresponding to creating superposition states with both levels #2 or #3, which superposition state would it likely go to and why?
   2. Can you generalize this to a rule as to which transitions between any two energy levels will happen and which will not happen? (Such rules are called “selection rules”, and as you can see here, arise from the symmetries of the wave functions in the different energy states. These occur in atoms much as you see here, with certain transitions being allowed, and happen strongly, while others are “forbidden” and do not happen.) 
8. As you saw and repeatedly asked about in the atomic discharge sim, an electron in an excited state in the atom can make a transition down to a number of lower levels, with the probabilities of going to different levels being different. In part 7, you saw that certain transitions are simply forbidden, but that does not tell you why allowed transitions might have different strengths. Consider the dipole moments produced by a variety of superposition states that have nonzero dipole moments, say 1 & 2, 1 &10, 1 & 16, 2 & 17, 2 & 3. Are they different? Can you come up with some approximate rules for predicting relative strengths of dipole moments? A superposition with a large dipole moment would correspond to a high probability of making a transition between those two states, and a small dipole moment would have a low probability. It is possible to calculate dipole moments and hence transition strengths precisely from the wave functions. 

Michelle K. Smith, Department of Ecology & Evolutionary Biology, Cornell University

(this summary was written by Sarah Gilbert, based on the article and associated materials cited below)

Brief summary of the level and subject of the course in which the activity is used

The target group is an undergraduate genetics course for majors.

Principles and practices the activity addresses

The activity addresses all of the practices and principles in Figure 1. The difficulty level is ramped up, so the students learn from easier questions and apply that to subsequent more difficult questions. The context is a case study—an interesting real-world application of genetics. Social learning is used in the form of student discussions about clicker questions.

Why I felt it was successful

The paper shows clear evidence of learning as a result of the activity.

How the activity was implemented in the course, including what were the student deliverables

The activity was implemented as a series of clicker questions with student (peer) discussion. Student deliverables are their individual answers to the clicker questions before and after peer discussion. The activity could be implemented as a worksheet activity with small groups of students, but the student deliverables would need to be designed for that implementation.

The teaching activity itself

The activity has been published in an open access journal: Michelle Smith, "," PLoS Biology 10 (3) (2012).

See clicker questions used in the activity here. There is more information in the article, including example homework and exam questions. Click to see full slides for a class.

Cutthroat trout in Colorado: A Case Study Connecting Evolution and Conservation

Sierra M. Love Stowell & Andrew P. Martin, University of Colorado, Boulder

See . 

Abstract

Evaluation of evidence is a key process skill for the core competencies of applying the process of science and using quantitative reasoning. This case study enables upper-division biology students to practice these skills by applying evolutionary concepts to a real-world conservation problem and make evidence-based decisions accounting for uncertainty in real data sets. Cutthroat trout have a long evolutionary history of allopatric speciation and a complicated history of movement by humans for subsistence, recreation, and conservation purposes. This case study engages students because it requires a fundamental understanding of evolutionary processes such as speciation and hybridization and raises questions about the value of native species and the goals of conservation efforts. In an interrupted lecture format that can be adjusted for one longer 75- or 120-minute period or two shorter 50-minute periods, students learn about the Endangered Species Act, the evolutionary and human histories of cutthroat trout, and examine figures in order to make recommendations for the conservation of cutthroat trout. This case study shares primary research in the field of conservation genetics with students and allows them to grapple with the complexity of the decision-making process in wildlife management. Students enjoy connecting information that may be abstract for many (evolutionary processes and analyses) to a system (cutthroat trout) that they find tangible and relatable. This case study will be useful for courses in conservation biology, fish biology, and evolutionary biology, and adaptable for other contexts such as general biology and genetics.

Evidence of success

As discussed in article, pre-post testing on the learning objectives and examination of student worksheets.

The activity

Worksheet that students complete working in small groups is given in pages below. The figures referred to are available in the CourseSource article supporting materials.

Student Worksheet. Cutthroat trout in Colorado case study

Learning Goals:

1. Understand how the Endangered Species Act treats evolutionary processes
2. Connect evolutionary concepts to wildlife management practice
3. Understand how different kinds of data will lead to different conclusions

Specific Outcomes:

1. Interpret figures such as maps, phylogenies, STRUCTURE plots, and networks for species delimitation
2. Identify sources of uncertainty and disagreement in real data sets
3. Propose research to address or remedy uncertainty
4. Construct an evidence-based argument for the management of a rare taxon

Introduction:

The Endangered Species Act of 1973

The Endangered Species Act was signed into law by President Nixon on December 28, 1973. It was designed to protect critically imperiled species from extinction as a consequence of human actions. The legislation is directed at species conservation; a species is considered eligible for protection if it meets at least one of the following criteria:

1. There is the present or threatened destruction, modification, or curtailment of its habitat or range.
2. An over utilization for commercial, recreational, scientific, or educational purposes.
3. The species is declining due to disease or predations.
4. There is an inadequacy of existing regulatory mechanisms.
5. There are other natural or manmade factors affecting its continued existence.

The legislation mostly operates by designating and protecting “critical habitat,” and undertaking additional measures such as captive breeding and reintroduction.

The ESA does allow the listing of subspecies and other groupings below the rank of species, so long as they constitute “distinct population segments … [whose members] interbreed when mature,” are “discrete” and “significant,” and face the “danger of extinction throughout all or a significant portion of [their] range.” Roughly one-quarter of listed taxa are subspecies, but management agencies are hindered by uncertainties about taxonomic designations. There are no standardized criteria for taxonomic designations. The status of hybrids under the ESA is also unclear because there is no official policy for how they should be managed.

Cutthroat trout

The cutthroat trout (Oncorhynchus clarkii) is a species of salmonid fish native to cold waters of the Rocky Mountains, the Great Basin, and the tributaries of the Pacific Ocean in North America. They are important game fish, especially for fly fishing. There are at least a dozen described subspecies of extant cutthroat trout, and multiple extinct lineages, each native to a major drainage basin. The subspecies are hypothesized to have diverged in isolation in drainage basins during the cycle of Pleistocene glaciations. As a species, they are separated by at least 3 million years of evolution from their sister species, the rainbow trout (Oncorhynchus mykiss). The subspecies hybridize easily with one another and with rainbow trout. All extant subspecies are under some form of state or federal protection.

Part I: The case of the misplaced trout

1. Based on the data (Figures 1-3), how many lineages of cutthroat trout were originally considered native to Colorado? What data do you find most convincing? Justify your choice.
2. Where are those lineages found on the landscape (Figure 4)? What explains this pattern (Figure 5)? What are other possible explanations?
3. What data do we need to uncover how many lineages there actually were? Design research to answer this question.

Part II: The case of Weird Bear Creek

1. The confusion generated by the publication of Metcalf et al. 2007 led researchers to turn to stocking records and museum samples of trout collected before stocking took off in Colorado. Based on the data (Figures 6 & 7), how many lineages of cutthroat trout are now considered native to Colorado? Do you find it convincing? Why?
2. The lineage native to the South Platte (the major drainage including Boulder Creek) is now confined to a single population of about 800 individuals in a three-mile stretch of stream in the Arkansas drainage. This population has low genetic diversity: Metcalf et al. (2007) detected only a single mitochondrial haplotype and low heterozygosity across 10 microsatellite markers. In hatchery stock, reduced survival, deformities, and albinism are common. Given what you know about evolutionary processes and the Endangered Species Act, what recommendations would you make to Colorado Parks & Wildlife, the state agency responsible for cutthroat trout management in Colorado?

Citations

Allendorf, Fred W., et al. "Intercrosses and the US Endangered Species Act: should hybridized populations be included as westslope cutthroat trout?." Conservation Biology 18.5 (2004): 1203-1213.

Behnke, Robert J. "Native trout of western North America." American Fisheries Society (USA) monograph no. 6. (1992).

Metcalf, Jessica L., et al. "Across the great divide: genetic forensics reveals misidentification of endangered cutthroat trout populations." Molecular Ecology 16.21 (2007): 4445-4454.

Metcalf, Jessica L., et al. "Historical stocking data and 19th century DNA reveal human‐induced changes to native diversity and distribution of cutthroat trout." Molecular Ecology 21.21 (2012): 5194-5207.

A clicker-based case study that untangles student thinking about the processes in the central dogma

Karen N. Pelletreau et al., University of Maine

Published in . 

Abstract

The central dogma of biology is a foundational concept that provides a scaffold to understand how genetic information flows in biological systems. Despite its importance, undergraduate students often poorly understand central dogma processes (DNA replication, transcription, and translation), how information is encoded and used in each of these processes, and the relationships between them. To help students overcome these conceptual difficulties, we designed a clicker-based activity focused on two brothers who have multiple nucleotide differences in their dystrophin gene sequence, resulting in one who has Duchenne muscular dystrophy (DMD) and one who does not. This activity asks students to predict the effects of various types of mutations on DNA replication, transcription, and translation. To determine the effectiveness of this activity, we taught it in ten large-enrollment courses at five different institutions and assessed its effect by evaluating student responses to pre/post short answer questions, clicker questions, and multiple-choice exam questions. Students showed learning gains from the pre to the post on the short answer questions and performed highly on end-of-unit exam questions targeting similar concepts. This activity can be presented at various points during the semester (e.g., when discussing the central dogma, mutations, or disease) and has been used successfully in a variety of courses ranging from non-majors introductory biology to advanced upper level biology.

The article provides details and discussion about the activity. The supplementary material with the article gives the implementation in two forms, one is a powerpoint file containing clicker questions and their follow up to use in a large lecture class, and the second is as a worksheet activity to use in a class without clickers. The worksheet version of the activity is given below. 

Example Worksheet B: This worksheet was designed to introduce the case study and related concepts in classrooms that do not use clickers.

Muscular Dystrophy Case Study

The Case

The Disease: Muscular Dystrophy (MD) is a group of diseases that cause progressive weakness and loss of muscle mass. In MD, abnormal genes (mutations) interfere with the production of proteins needed to form healthy muscle. There are many different kinds of MD. Symptoms of the most common variety begin in childhood, primarily in boys. Other types do not surface until adulthood. Some people who have MD will eventually lose the ability to walk. Some may have trouble breathing or swallowing. There is no cure for MD, but medications and therapy can help manage symptoms and slow the course of the disease.

The Genetic Cause: Mutations in the gene for dystrophin cause MD. Normally, muscles are made up of bundles of fibers and a group of interdependent proteins along the membrane surrounding each fiber helps to keep muscle cells working properly. Dystrophin is one of the proteins involved in this process. When the amino acid sequence of dystrophin is changed due to a mutation, muscles do not function properly and the result can be MD.

Your Task: Suppose you are a genetic researcher. You are working with DNA samples from two brothers. Liam has MD, but his brother Elijah does not. The sequence of Elijah’s gene is shown below. You have identified 5 differences in the dystrophin gene as indicated in the grey boxes. Your task is to predict which of the five mutations in Liam’s DNA is most likely to cause MD.

Note 1: This does not represent the actual gene for dystrophin– this is a modified model that simplifies the case study.

Note 2: You should assume that a protein product is made for Liam.

Muscular Dystrophy Case Study

Instructions

Record your answers on the Muscular Dystrophy Case Study Worksheet.

Step 1: Determine the sequence of the final mRNA product that will be transcribed from Elijah’s gene and record this on the worksheet in the space provided.

Step 2: Determine the amino acid sequence of the protein product made from Elijah’s gene and record this on the worksheet in the space provided.

Step 3: Determine how each mutation in Liam’s gene will affect the protein synthesized from the gene.

Step 4: Based on the information from steps 1-3, complete Table 1 on the MD Case Study Worksheet.

• In column 2, indicate if the mutation (1-5) is the likely to be the cause of MD (Y=yes, N=no).
• In column 3, explain your reasoning. Be sure to include a description of how the mutation would affect the protein synthesized from Liam’s gene.

Step 5: Once you have identified the mutation that is most likely responsible for causing MD, complete Table 2. Explain how the mutation will specifically affect the processes of DNA replication, DNA transcription into RNA, and translation.

Muscular Dystrophy Case Study Worksheet

What is the sequence of the mature mRNA product that will be transcribed from Elijah’s gene?

What is the amino acid sequence of the protein product made from Elijah’s gene?

Table 1

Table 2

James Scoates, Dept. of Earth, Ocean and Atmospheric Sciences, University of British Columbia

(this summary was written by Sarah Gilbert, based on the video and materials cited below)

Brief summary of the level and subject of the course in which the activity is used

The course is Introductory Mineralogy, a second-year geology course. There are about 100 students in the class and the activity is run towards the end of the semester.

Principles and practices the activity addresses

In this activity, students apply mineral ID skills that they have learned in the course to minerals representative of the 10 different stages of mineral evolution from the first-formed minerals present in meteorites to modern biominerals (4.56 billion years of Earth history). The goal of the activity is for students to discuss, evaluate, and appreciate how the number and composition of minerals have evolved throughout geological time.

The activity addresses all of the practices and principles in Figure 1. The students are practicing expert analysis and synthesis using knowledge and skills they have learned in the course with the feedback from the instructors and teaching assistants. Motivation is built into the activity in a variety of ways (there are clear reasons why each step is important for producing the poster on the geological environments in a stage of mineral evolution, students are reminded that they have the knowledge and skills to successfully complete the activity, the activity itself is Real World in a big way and the students can see how it will help them be successful in future geology courses, ...). Social learning is used in both the mineral identification step (student pairs) and in the poster step (group of students).

Why I felt it was successful

The students are very engaged in the activity and the final product (posters showing the geological environment(s) operational during the stages of mineral evolution) were good quality.

How the activity was implemented in the course, including what were the student deliverables

The activity consists of 4 parts – the completed 2-page activity form is to be handed in at the end of class. Part 1 – identification of an unknown mineral – is completed in pairs; all other parts are done by sharing and discussing information with other members of a specific stage in mineral evolution (groups of 5-12). The ultimate deliverable is a schematic drawing on poster board of the geological environment(s) operational during that stage of mineral evolution. At the end of this synthesis activity the instructor wraps up by referring to course goals and highlighting skills and knowledge that students have just demonstrated.

The teaching activity itself

See the video and associated PDF files . See the activity worksheet here.

Warren J. Code, Associate Director, Science Centre for Learning and Teaching (), University of British Columbia in Vancouver, Canada

Summary of level and subject

Students sketch the graph of a piecewise continuous function based on a described scenario. This activity is intended for students in their first (differential) calculus course, as a prelude to discussions of function continuity; even for students who have previously taken calculus, piecewise-defined functions may be unfamiliar even though these functions provide important examples in understanding a technical definition of continuity based on limits. Learning goals that may be addressed include:

• Interpret piecewise continuous graphs in terms of continuity at a point, left- and right- hand limits.
• Convert to/from a piecewise-defined function expression and its graph.
• Sketch graphs of simple functions based on provided data about rates, certain values, and other information.
• Convert a “word problem” to one or more mathematical representations (graphs in particular).
• Interpret a constant rate as having a straight-line graph (and vice versa).
• Attend to important features of a graph when sketching (key points or parts of a shape) instead of precise scale drawings.

Principles and practices the activity addresses

The activity provides students a scaffolded approach to learning about piece-wise defined functions and their graphs (building blocks for later discussions of continuity), offering practice and feedback on a couple of key skills of mathematicians: converting between representations and sketching graphs to emphasize important mathematical features (not precision drawing). Students who are unfamiliar with piecewise-defined function notation or conventions for drawing graphs with discontinuities can still attempt drawings based on their prior knowledge of linear relationships (as described in a “word problem”) and their graphs. Meanwhile, there is enough challenge relative to the time given that students who are more familiar with the fundamental concepts will still spend time practicing (the back of the worksheet has a contrasting modified case of the initial problem). Students are tasked with some individual thinking and writing/drawing that on their worksheet to activate their prior knowledge and start practicing, and then feedback comes from a combination of peer discussion, clicker response information, and the instructor’s comments based on these.

Why I felt it was successful

In my differential calculus for commerce and business applications course (taught multiple times), all groups were able to start some sort of graph while the fastest groups (a minority) were able to complete a graph for the back side of the worksheet (a similar second task that builds on the first). Student responses were distributed over common misconceptions/guesses about piecewise-defined functions and their graphs, and these were easy for me to diagnose by looking at their attempted graph (e.g., did they use circles and dots for points of discontinuity, did they connect the “gap” at the discontinuity to make the graph look continuous). This also provided a useful example for discussing continuity throughout the course and I was able to refer back to it as a touchstone.

How the activity was implemented in the course, including student deliverables

This activity appeared early in the course, around the second week. As part of class time, students were provided with the worksheet. In semesters where worksheets were collected, that would form part of the deliverable, but the main deliverable was to answer clicker questions related to their worksheet solutions. Students were asked to spend time on their own and then compare with a partner after they had produced something, and clicker questions using Peer Instruction (vote, then discuss and revote if necessary) were used at various points to check in on progress and provide instructor feedback to the class in general (based on my sense of progress from circulating during the activity). Depending on the variations used (see below), this could run from 15 minutes to 30+ minutes in terms of class time.

Materials for this activity

The next page shows the worksheet which students were provided, and the page beyond summarizes the clicker questions used to support the worksheet activity.

Variations

• Asking students to also write down the cost function (which would be defined piecewise) can be included, or saved for another day, depending on the time available.
• To emphasize limit notation or help build towards the piecewise-defined notation, an additional task like “Use limit notation to describe the behaviour of the paint cost function you drew at 5L, 2L and 0L.” can be included or used in a follow-up activity.
• The notion and explanation of “minimum cost” can be omitted from the worksheet text; this makes the problem somewhat ill-posed as different cost functions are possible for someone who is not being efficient in their purchase; this can be considered a challenge for students who are already thinking about careful definitions (important mathematical thinking!) but again this would likely result in further time needed for elaboration.
• Litres can be replaced by quarts or other volume unit for local flavour.

Paint Store - Worksheet

[Course, Date]

Names and student numbers for your group: [if worksheet is collected]

There is a special paint store with only one size of bucket that will sell exact amounts of paint, meaning they will partially fill a bucket to your exact specifications (for example, you could buy 1.34L of paint, or 1.345623L of paint). Each bucket can hold a maximum of 5L (L = litres) and costs $6.00, while the paint costs $10.00 per litre. (Assume we are only buying one colour of paint, and that there is a large fine for not using all of our paint, so that we always want to buy the exact amount of paint and no extra.)

Task 1: Draw a graph that represents the minimum cost for a range of 0L up to 12L.

[Back of same sheet of paper; leave lots of space below each task]

Task 2: Suppose the store also offers full, sealed buckets of exactly 5L of paint for a special price of $40 (since they do not require the careful filling time of the partial buckets), but you can still purchase partially-filled buckets as well at the same prices as before. Draw a graph for the same range of 0L to 12L.

Clicker questions

A short sequence of clicker questions exploring student interpretations of their graph at specific points, including points around what should be a discontinuity.

• How much will it cost to buy 1L of paint? (options could be: $6, $10, $16, “Another amount”, “I am not sure.”)
• How much will it cost to buy 4.9L of paint? (options could be: $55, $56, $61, $62, “I am not sure.”)
• How much will it cost to buy 5.1L of paint? (options could be: $56, $57, $62, $63, “I am not sure.”)
• How much will it cost to buy 5L of paint? (options could be: $56, $57, $62, $63, “I am not sure.”)

One clicker question to check on the graph shapes and explore misconceptions about graphs and in particular graphs with discontinuities. These are all based on actual student responses; it is important to provide something that looks like a sketch for each of the options since your graph will not be identical to there; this also helps to emphasize the idea of producing a sketch that emphasizes key features (like a mathematician would draw) as opposed to a precise, machine-drawn diagram. The red text was added as further follow-up in checking on the correct values (response choices were displayed using a document camera so this sort of annotation was possible).

Ido Roll, University of British Columbia

A brief summary of the level and subject of the course

• A graduate level Statistics course.
• Students come from a very strong qualitative background, mainly in library studies. 

Which of the principles and practices on fig 1, the activity addresses?

• This activity focus on perceptions of what expertise in statistics means, as defined on Page 7: "Disciplinary expertise (…) includes recognizing what decisions need to be made in relevant contexts, along with the tools, reasoning, and knowledge of the discipline to make good decisions"
• By understanding that Statistics offer a set of tools, rather than a set of truths, the activity also targets students' Motivation towards the course and the field. 

Why you felt it was successful

• Before implementing this activity, students in the course were very anxious about getting things “right”. This builds on years of negative experiences with math. Subsequently, many students dropped the course.
• Students approached me following this activity saying that it changed their perception of Statistics and alleviated a lot of their anxiety. Students also refer to this activity later in the term, and attrition is no longer a challenge. 

How the activity was implemented in the course, including what were the student deliverables

1. The activity is the very first thing that we do in class. The only thing that precedes it is me saying my name. 
2. Instructor acknowledges that people have many reasons for taking the class. Also acknowledges that there are many ideas about what Statistics is and why it is important. 
3. Instructor describes several things that statistics, and in general, numbers, can mean to people: necessary evil (broccoli), a key to the mysteries of data (key), a friendly approach to understanding the world (buddies), the ultimate villain (Darth Vader), a meaningless set of numbers (stream of digits), etc. 
4. Instructor gives students five minutes to reflect on what numbers and statistics mean for them and why they are taking the course. Students are asked to find a visual representation that demonstrates that.
5. Students who want to share, share their representations and explain why they chose these.
6. Instructor explains that Statistics is a set of tools that help us identify meaningful patterns in data. Instructor further explains that there is no one “correct” statistics, only useful statistics that is relevant in context (based on data, assumptions, questions).
7. At the end of class, students write a 1-minute paper about how the course matches their goals and what their adjusted expectations are. 

The teaching activity itself

Two-stage review using a card-sorting activity to promote students making connections across concepts

Megan Barker, Simon Fraser University

Where implemented

Could be used in any level/discipline. I have used it in intro-level biology (enrollment 100–450 students).

Principles and Practices

• Addresses prior knowledge, motivation, and disciplinary expertise.
• Implementation uses both social learning, tasks/questions + deliverables.

Why I felt it was successful

• Active engagement of a large proportion of students: the classroom had students actively working on individual tasks, then had many voices on-task in small groups. This is distinct from other review sessions where most students are passively listening, and/or do not have course material to engage with.
• “Data” from student deliverables: student responses handed in from their groups demonstrated higher order thinking and deeper learning (synthesis/connections of ideas into categories).
• Modelled from other evidence-based approaches (Two-Stage Review (Maxwell, McDonnell, Wieman 2015 JCST) and card-sorting activities (Smith Combs Nagami et al, 2017 CBE-LSE))

Activity & implementation in the course

Background: I have developed an approach for a modified two-stage review session at the end of the course, prior to final exams. My students value a dedicated class-time review session, but this time can be easily squandered and/or directed only towards a small proportion of the students. Instead, I have borrowed ideas from two-stage review and card-sorting tasks. This activity is not for grades (but can be for participation grades).

When in the course: In the last regular class of the semester, typically ~1 hour.

Individual phase: Students individually complete a small subset of test-style questions. In my course, I give them 15 multiple choice questions selected across the whole course material.

Deliverable #1: They hand in their responses on a worksheet (or via clickers).

Group phase, part 1: they join into groups of four, and (rather than re-answering the questions), they are instructed to organize the questions into ~3 categories of their own choosing, and to write the names for categories on a sheet of paper (or a worksheet).

Group phase, part 2: Without taking up the first categories, I ask them to re-organize the questions into a completely different set of (named) categories of their own choosing.

Deliverable #2: Students hand in their worksheets (at this point or at the end).

Coming together: We take this up as a class, with students reporting out what categories they chose, and their reasoning. Generally, the first set of categories is more superficial – e.g. questions about plants, questions about animals, etc. The 2nd set of categories is deeper than the first – e.g. cognitive difficulty level of the question, cross-cutting theme, skills required to answer the question, etc. Instructor facilitates the discussion by making connections to exam study approaches, value of social learning, and metacognitive practices.

Bonus outcome, for the instructor: Pre-post data. The individual phase can be used as a concept inventory post-test, matched to the start-of-term pre-test built into a 2-stage review.

Bonus outcome, for the students: Personalized exam prep jump-start. Individual student answers to the individual phase can be posted on their course LMS (e.g. in the gradebook), with targeted questions for them to work on based on which questions they were correct or incorrect.