Category: Labs

A First Crack at Introductory Lab for Physics and Astronomy Majors (Physics 181 Lab)

This past semester saw my first attempt at teaching introductory lab for physics majors (Physics 181 Lab at UMass Amherst). I worked with Chris Ertl, leveraging his expertise in developing labs for Physics 131 inspired by Course-based Undergraduate Research Experiences (CUREs) common in biology1. In CURE lab courses, students explore authentic scientific questions and share their results with the broader scientific community. Development of such curricula is comparatively simple in biology as almost any soil sample will include microorganisms unknown to the literature.

While true CUREs are difficult to construct in physics, as most authentic physics research questions are beyond the reach of introductory students, we strove to incorporate the ideals of this approach as well as synthesize it with both the AAPT’s Recommendations for the Undergraduate Physics Laboratory Curriculum2 and the thoughts expressed in Introductory Labs: We can do Better3 article from Physics Today’s January 2018 edition. We also owe a lot to the prior instructor, Scott Hertel. The resulting course focused on the following goals with the aim to make the experience as close to that students will see in future lab work:

  1. Physics-identity promotion and acculturation: The literature is very clear on the importance of the development of physics-identity, particularly with regards to students whose identities are not traditionally associated with physics4,5. We explore different careers physicists purse from the traditional academic/lab roles to comic-strip authors. Within the research sphere, we discuss the different modalities of theoretical, phenomenological, computational, and experimental along with a bit on what the day-to-day lab work is like for each group. Finally, we discuss some practical aspects of being a physics student including the concept of REUs, getting involved in research and TAing including the financial aspects (that you get paid for REUs and graduate school for example). This last point particularly important for first-generation and international students who may be less familiar with the structure of physics education at the university level in the U.S.
  2. Scientific philosophy and values: Students received explicit instruction into some of the fundamentals of scientific philosophy, such as the logical impossibility of proving things true and the differences between inductive and deductive reasoning. Moreover, helping students understand and appreciate that experiments almost never work the first time was baked into the course from the foundations. Students also engage with the fundamentals of modeling: what variables are important, what can be ignored, etc. as they build their own models from their data.
  3. No “cookie-cutter” labs: All the labs had minimal instructions with regards to procedure forcing students to design the procedures themselves.
  4. Construction of their own apparatus: Instructors of more advanced labs had commented that students in these courses were not comfortable with using equipment as basic as C-clamps. My hypothesis was that this discomfort arose from the structure of prior lab courses: historically, students have entered the lab to find the setup already established by the lab instructional team. Instead, we had, the more authentic, shelf of materials which students could use to construct their own apparatuses.
  5. Understanding uncertainties: Students were explicitly taught the difference between statistical and systematic uncertainties in an explicitly frequentist framework. Moreover, students were expected, by the end of the laboratory, to
  6. Refinement of Procedures: Dovetailing with goals 2-5 above, and inline with the recommendations for CUREs, students are always given time to refine their procedures and try again. Of course, refinement takes time. As a consequence, we only did five labs over thirteen weeks with each lab taking two or three weeks to complete.
  7. No “black boxes”: In order for students to achieve goals 4-6, students must fully understand and be able to calibrate their measurement tools. As such, only the most basic experimental tools are used: rulers, scales, protractors, timers, etc. This is in distinct contrast to prior iterations which used a lot of electronic measuring tools. My issue with these tools is that students can neither innovate nor really understand the uncertainties involved.
  8. Exposure to different subfields of physics: As described in Exploring subfield interest development in undergraduate physics students through social cognitive career theory6, many students are unfamiliar with most physics subfields beyond the “popular” upon entering higher education. Thus, we strove to include labs from multiple subfields including astronomy and granular materials etc. to both expose students to new fields and/or excite those who may already have such an interest.
  9. Exposure to python as a data analysis tool: This course is not designed to be an introduction to programming course – we have one of those which comes later. The programming goals of 181 Lab are simply to expose students to a python programming environment and to begin to get comfortable with manipulating data through text commands. I use the pandas python data analysis library due to is superficial similarities to spreadsheets which most students have at least opened and used in a superficial way.

The result of our collaboration was, I must say, one of the most successful first attempts at a course I have had in a long time. While there are, of course, things to change in the next iteration, I am excited to see how this course develops. Once it is more mature, I will create a dedicated page.

  1. Atreyee Bhattacharya, Pamela Harvey, and Perri Longley, CURE | Course-Based Undergraduate Research Experience (CURE) | University of Colorado Boulder, https://www.colorado.edu/research/cure/home. ↩︎
  2. D. MacIsaac, Report: AAPT Recommendations for the Undergraduate Physics Laboratory Curriculum, The Physics Teacher 53, 253 (2015). http://scitation.aip.org/content/aapt/journal/tpt/53/4/10.1119/1.4914580?ver=pdfcov. ↩︎
  3. N. G. Holmes and C. E. Wieman, Introductory physics labs: We can do better, Physics Today 71, 38 (2018). https://physicstoday.scitation.org/doi/10.1063/PT.3.3816. ↩︎
  4. E. W. Close, J. Conn, and H. G. Close, Becoming physics people: Development of integrated physics identity through the Learning Assistant experience, Phys. Rev. Phys. Educ. Res. 12, 010109 (2016). ↩︎
  5. S. Hyater-Adams, C. Fracchiolla, N. Finkelstein, and K. Hinko, Critical look at physics identity: An operationalized framework for examining race and physics identity, Phys. Rev. Phys. Educ. Res. 14, 010132 (2018). ↩︎
  6. D. Zohrabi Alaee and B. M. Zwickl, Exploring subfield interest development in undergraduate physics students through social cognitive career theory, Phys. Rev. Phys. Educ. Res. 21, 020109 (2025). ↩︎

Lab groups and peer evaluations

This past year, I have been working to develop a series of labs that focus on scientific skills, as opposed to teaching physics content. These changes are motivated in part by the pandemic: I want to have authentic laboratory experiences that students can complete at home with limited resources. However, these reforms are also motivated by the literature which suggests that lab is better suited to the teaching of such skills as opposed to content:

  • Holmes, Natasha G., and Carl E. Wieman. “Introductory Physics Labs: We Can Do Better.” Physics Today 71, no. 1 (January 1, 2018): 38–45. https://doi.org/10.1063/PT.3.3816.
  • MacIsaac, Dan. “Report: AAPT Recommendations for the Undergraduate Physics Laboratory Curriculum.” The Physics Teacher 53, no. 4 (April 1, 2015): 253–253. https://doi.org/10.1119/1.4914580.

Lab groups are one of the necessities of such a large class. In order to respect the TA’s time and keep the grading load manageable, students must turn in reports as groups. Fortunately, I also think that learning to work in a scientific team is also an important goal of the lab experience.

This past semester, I have been trying to use Moodle to manage the lab groups and CATME to do peer evaluations. However, this has yielded two problems:

  1. The TAs must keep the lists in Moodle up to date and there is an unclear chain of command with regards to group management. Also, this requires a rather sophisticated understanding of Moodle and makes changing/managing groups difficult.
  2. The CATME protocol, while fantastic, is, I think, insufficiently transparent. Moreover, I must manage it. This is, frankly, too much load for me. I need a system that the TAs can successfully manage on their own.

I really like the multiplicative nature of the CATME results. A plan with which I am currently toying involves:

  • Have a number of points equal to the number of members in the team.
  • Each team member would distribute these points to their team members. Perhaps this would be done for a few different categories.
  • There would also be one optional point that could be given to someone who really deserves an extra boost. This would be a bonus: if everyone in the team neglects to do it, they will still all get ones (i.e. their score would be equal to their actual grade).
  • The result would be scaled in such a way that the final multipliers are between 0.7 or so and 1.05.

Obviously, this needs to be flushed out, but there are some key points for improvement here.

Data Modeling Lab Based on COVID-19 for IPLS Students

When UMass-Amherst decided to go to remote learning after spring break, I needed one more lab for my Physics 132 – IPLS II course. This course has a traditional setup where the lab is run semi-autonomously from the “lecture” portion of the course. For the last two iterations, however, the lab has been run with a different focus based on data analysis. Thus, a lab focused on understanding the exponential growth patterns and fitting the parameters fit well with our education objectives and could be done with publicly available data.

While this may not be “physics” per se, I think that such a lab makes sense:

  • It uses all of the skills our students have been developing over the course of the semester.
  • It is topical.
  • It is probably of interest to the predominately life-science students who comprise the student population of 132.
  • It will hopefully help students see that the skills they learned in physics lab are not unique to physics, but instead valuable to all of science.

The lab we gave to students can be found here as as pdf. Feel free to use etc. If you are an instructor and would like access to the full suite of materials including the data we used, the solutions, and rubric, please complete this form and we will get them to you.

A new direction for the Physics 132 labs

During the Spring 2019 semester, in addition to several changes in the lecture portion of the course, Paul Bourgeois, David Nguyen, and I continued to make changes to the laboratory portion of Physics 132. Motivated by this article from Physics Today, we decided to make our labs much more focused on teaching fundamental data analysis skills as opposed to physics concepts. We also added structural changes to the lab portion to promote in the students a sense of importance and ownership of what we were trying to teach. In general, I think that these changes were, by the end of the semester, positively received and provide a strong way forward for future lab developments in Physics 131 and other courses within our department.

Continue reading A new direction for the Physics 132 labs

Thinking about integrated labs in the Team-Based-Learning Format of P131

As we near the end of the semester, Physics 131 is once again finishing up with a unit on the statistical interpretation of entropy (not a typical topic for an introductory algebra-based course). This unit gets started with two labs: one systematically playing the famous Monty Hall problem and a second models the free expansion/compression of a gas using coins. While I do not have strong evidence for this belief, I feel that these two labs are the strongest two labs we do all semester. Students seem to really engage with these two labs and the act of doing the experiments really seems to add to student understanding in ways I do not see with other labs in the course. Even our much celebrated lab investigating the bio-mechanical ground-reaction forces of the human jump doesn’t seem to engage our students as much. Why? What is the “magic sauce” of these two labs? How can we modify the other labs of the course to achieve these same ends?

Continue reading Thinking about integrated labs in the Team-Based-Learning Format of P131