Revamping Undergraduate Introductory Physics Laboratory - Comments

[ZapperZ]

I've started my own personal pet project in trying to suggest a possible revamping of the often dreaded intro physics lab. My philosophy here is two fold:

1. Teach skills in how we arrive at how things behave

2. The students shouldn't be encumbered with "theories" that they need to either "prove" or verify. So the experiments are meant to be done without them even being aware of the physics behind the experiments.

As always, I welcome feedback. I have no idea where this is going. I've thought about contacting a few universities around here to see if we can get some funding to try it out, but with my "day job" being what it is, I just don't have the time.

Zz.

 

[mgb_phys]

Excellent article.
There is the Nuffield Physics program (might be a UK only?) which tries to bring the learning from trying things out approach to labs. Very much like your suggestion - here are some weights, here is some string, find out about pendulums.

There is also a need for a 'tools of experimental physics' class, how to use an oscilloscope, read a vernier and basic experiemntal statistics.

Drop the experiments that don't work. Particularly 'classic' experiments like Millikan's oil-drop, Cavendish's 'G' and anything else when the write-up consists mostly of explaining why you didn't get the correct result.

 

[ZapperZ]

Excellent article.
There is the Nuffield Physics program (might be a UK only?) which tries to bring the learning from trying things out approach to labs. Very much like your suggestion - here are some weights, here is some string, find out about pendulums.

There is also a need for a 'tools of experimental physics' class, how to use an oscilloscope, read a vernier and basic experiemntal statistics.

I think the experiments that I'm thinking of would also be suitable for the "general students", meaning these aren't meant solely for physics/science/engineering majors. Those students will eventually get more laboratory exercises to refine their skills, but for other students, the intro physics lab (and other intro science labs) are the only place where they actually get to do something like this AND actually figure out how to describe nature quantitatively. This is what is lacking for, say, http://physicsandphysicists.blogspot.com/2008/11/what-is-worse-than-lost-soul-ignorant.html" to the point where they do not realize that it requires a lot of "critical thinking" to do science.

So these are not really "physics experiments", but rather, "Nature experiments".

Zz.

 

[Bystander]

I think the experiments that I'm thinking of would also be suitable for the "general students", meaning these aren't meant solely for physics/science/engineering majors.(snip)

"One size fits all?" You ain't the first to dream that dream. The ugly truth of the matter is that analytical thinking isn't just unfamiliar to the non-majors --- it is anathema to them, their fields, and to advisors and faculty teaching in those fields or having backgrounds in those fields.

"Hooking" their interest is the first big hurdle to at least demonstrating analytical, rigorous approaches to investigation, measurement, and problem solving. It's been twenty years since I abandoned "the dream" in frustration. Something I didn't examine in detail that might appeal to the "free lunch" aspect of humanities majors' training is playing with loaded dice, roulet wheels, slot machines and the like --- sort of sucker 'em into examining ways to rig coin tosses, bar bets, and other gambling games, and from there to probability, Gaussian distributions, measurement methods, and then into analytical problem solving.

Don't hold your breath --- the pub-crawling days are long past, but I never had any luck keeping the hustlers' interests when they were financing their drinking habits, augmenting pool table incomes, and other things, and they were far more motivated to learn than are most humanities majors.

 

[physics girl phd]

"One size fits all?" You ain't the first to dream that dream. The ugly truth of the matter is that analytical thinking isn't just unfamiliar to the non-majors --- it is anathema to them, their fields, and to advisors and faculty teaching in those fields or having backgrounds in those fields.

Wow! Isn't that a negative, elitist view... and I disagree!

I teach the general education intro-class for non-scientists at our university, and it doesn't even have a lab. As a result, I virtually eliminated lecturing in favor of having students read before class (they are quizzed on reading via an online system) in preparation for team-learning activities done in the lecture hall, including small simple labs with readily available supplies. My feedback from the students has been great, and their performance seems to be better than it used to be (I'm presently taking data on both their attitudes and their learning gains).

In fact... I'm learning from these experiments too. Because I'm looking for cheap supplies (I buy them out of my pocket, and I reuse what I can term to term), I get creative and try things out I think might work (but sometimes aren't sure about). Sometimes, with simple supplies and untested experiments, the results AREN'T what I or students expected... and they do notice and have good questions. Students who did take physics before are seeing it in a new light, because the activities aren't using Pasco sensors, etc, that can cause labs to be written up into cookbook "recipes." (And students on the pre-med/vet and engineering tracts complain about the labs offered in the department because they are so cookbook... our lab director has tons of Pasco equipment he doesn't want broken, but it isn't in the budget to replace simple things like meter-sticks).

Also: Faculty in other fields do what their students to gain analytical skills. Where do you get the idea they don't? Analytical skills might very a bit from field to field (becoming less mathematical perhaps in some fields), but many of the basics remain the same.

I will grant one aspect to your post... one size probably doesn't fit all (it never does in clothing... does it?)... I'd add on more mathematical aspects (better error analysis, etc) for students who are planning to pursue certain fields. But that doesn't mean we should neglect our responsibility to nurture critical thinking and stereotype students who are still growing.

Sorry ZZ... I don't have control of the lab equipment at our institution... if I was, I'd be there with you and your quest for $$!

 

[ZapperZ]

I too have taught a physics class for non-science major that was populated mainly by premeds. I can tell that there were MANY that were interested in what they're doing, provided that they are presented in ways that THEY can understand, not in ways that another physicist can understand. So based on anecdotal evidence alone, I do not have that skeptical view on our ability to get SOME of the students to appreciate the critical thinking that one can gain out of a physics class.

These are the same people that we count on to make science-related decision, either by electing representatives that reflect their views, or in support of funding for various science projects. The fact that we are saddled with the current situation means that the task of teaching them about science and critical analysis haven't been done properly. And I see many efforts to try to remedy this. Richard Muller's Berkeley's course and book "Physics for Future Presidents" is one such clear example, and got quite a bit of publicity leading up to the presidential election.

Unless we want to be fatalistic about it and just simply throw our hands up in the air, one has to try something, even at a small scale, one person at a time. I definitely try to put my money where my mouth is, since I try to volunteer my services each time there's an involvement in introducing physics, and what I do, to the public, students, etc. To simply give up and not even attempt at doing something is not an option for me.

Zz.

 

[Moonbear]

On that same topic of teaching to the non-physics majors, one reason that biology departments require their students to take physics courses is that the curriculum lends itself so well to analytical thinking and problem-solving that it's a good course to teach that. These ARE skills that these other majors need, but the undergraduate courses don't often teach them.

I don't agree that labs should be eliminated simply because the predicted result is not obtained. Rather, students should be taught that the lab report is NOT about making excuses for the lack of predicted results, but in how to apply their results to their hypothesis. When I taught undergraduate biology, we PURPOSELY included a lab in which we knew the results would not fit the predicted. The students were supposed to conclude that their hypothesis was not supported and explain a new, alternative hypothesis based on their actual findings. The learning objective was NOT to teach them to write a formulaic lab report but to learn how to formulate, test and refine an hypothesis...in other words, how to do science.

That said, Zz, good luck. The biggest problem is that while departments support the ideology of creating new labs, new courses, updating curricula, etc., they provide very little in terms of financial support to do those things.

 

[jday]

I am currently involved in an initiative at my institution in which we are actively striving to achieve the most effective, evidence-based science education possible. So, I thought I'd add an unstructured thought or two (or more) to the discussion here.

First of all, I'm always excited to learn about this kind of endeavour. Hooray for efforts to improve physics education! Even if we're not pumping out physicists, we want all of our university and college grads to be critical thinkers.

It is important that one explicitly establishes what students should learn - lay out learning goals for the individual course in operational terms of what students should be able to do if they learned all you would like them to. These goals should really(!) include everything you hope students to learn: concepts, vocabulary, specialized skills, critical thinking skills, etc. Establishing clear goals greatly informs the design of the curriculum, as well as teaching and subsequent evaluation methods. If you are interested in examples of the learning goals we've created for our freshman physics (majors) labs, ZapperZ, I'd be happy to share them with you.

One should also make an effort to scientifically measure what the students are actually learning. Sharing personal teaching experiences is great, but if you want to convince your colleagues that the revamp is required and/or is working, then you almost certainly require quantitative measures of the improvement in student learning. As I'm sure you know, data trumps anecdotes like rock beats scissors. Creating the right kind of assessment tools, however, is easier said than done - it's an iterative process, assessment validation takes time, etc - but it's worth the effort in the end.

If you are interested in learning a little more about the sorts of changes being made at another institution, check out the paper titled "Teaching Expert Thinking" http://www.cwsei.ubc.ca/resources/instructor_guidance.htm" and the references therein. This short little article details one of the things ('invention activities') that has gone into our revamped physics labs.

 

[mgb_phys]

I think the experiments that I'm thinking of would also be suitable for the "general students", meaning these aren't meant solely for physics/science/engineering majors.

The Nuffield course covered O'Level (ie 14-16year old) and A'Level (16-18) and didn't require calculus so should be suitable for non-physics majors at college.

 

[ZapperZ]

It is important that one explicitly establishes what students should learn - lay out learning goals for the individual course in operational terms of what students should be able to do if they learned all you would like them to. These goals should really(!) include everything you hope students to learn: concepts, vocabulary, specialized skills, critical thinking skills, etc. Establishing clear goals greatly informs the design of the curriculum, as well as teaching and subsequent evaluation methods. If you are interested in examples of the learning goals we've created for our freshman physics (majors) labs, ZapperZ, I'd be happy to share them with you.

I think in my article, I had tried to convey the goal. Strangely enough, it really isn't about learning a particular aspect of a principle of physics. While there is physics involved, it is more on a "sub-conscious" level. Rather, I want the students to discover the relationship between two variables. In the case of the spring-mass system, let's say, it is between the period of oscillation and the amount of mass. To me, that's the most important goal. How does changing one, affect the other? Can the student quantify the relationship?

I find this extremely important because in real life, many people attribute one or more thing as the cause of another. People say "oh, such-and-such is bad because it causes this". This is exactly a similar situation as what we do in a lab, because one is relating how one parameter causes a change in another. Everything about our decision-making is based on us knowing the relationships between different things and how they affect one another. The discovery of not only the exact relationship between them, but also that there IS a relationship in the first place, to me, is one of the most important skills that one can have. That is why, if you notice in all the experiments that I've suggested, I've emphasized such a discovery first and foremost. Such ability requires almost no knowledge of physics. Even how to phenomenologically quantify the relationship requires almost no knowledge of physics.

One should also make an effort to scientifically measure what the students are actually learning. Sharing personal teaching experiences is great, but if you want to convince your colleagues that the revamp is required and/or is working, then you almost certainly require quantitative measures of the improvement in student learning. As I'm sure you know, data trumps anecdotes like rock beats scissors. Creating the right kind of assessment tools, however, is easier said than done - it's an iterative process, assessment validation takes time, etc - but it's worth the effort in the end.

The measure of what the students have learned is their ability to flat out state how A depends on B, and what would happen if one varies B. A "bonus" measurement would be on how close was the outcome based on what they expected before performing the experiment. It is always a tremendous lesson to realize that the result is different than what one had predicted. To me, this is THE part where we learn, i.e. when we're wrong. The balloon in the train part is all about this. This is how science progresses, and that experiment is an opportunity to show that.

Zz.

 

[jday]

I think in my article, I had tried to convey the goal. Strangely enough, it really isn't about learning a particular aspect of a principle of physics. While there is physics involved, it is more on a "sub-conscious" level. Rather, I want the students to discover the relationship between two variables. In the case of the spring-mass system, let's say, it is between the period of oscillation and the amount of mass. To me, that's the most important goal. How does changing one, affect the other? Can the student quantify the relationship?

You are right, I believe, in that it isn't about learning a particular aspect of a principle of physics: we want to teach our students to 'think like a physicist" (even if they aren't thinking about physics). The primary goal of first-year labs, in my humble opinion, is that students develop skills and attitudes that will be of value no matter what their later academic path may be. They should learn how to make observations and measurements, how to build models that fit those measurements, and derive meaning from the success or failure of those models. Your article does convey the goal of the labs, and I simply meant to emphasize that I see importance in making these goals explicit to the students (but I'll concede that this might be a matter of personal preference). One might share these goals with the students on day one and then refer back to them throughout the term as they are addressed. As an example closely related to the skills you mention, a learning goal might be: you (the student) will be able to analyze an experimental situation in order to identify the variables that might control the phenomenon being studied.

I find this extremely important because in real life, many people attribute one or more thing as the cause of another. People say "oh, such-and-such is bad because it causes this". This is exactly a similar situation as what we do in a lab, because one is relating how one parameter causes a change in another. Everything about our decision-making is based on us knowing the relationships between different things and how they affect one another. The discovery of not only the exact relationship between them, but also that there IS a relationship in the first place, to me, is one of the most important skills that one can have. That is why, if you notice in all the experiments that I've suggested, I've emphasized such a discovery first and foremost. Such ability requires almost no knowledge of physics. Even how to phenomenologically quantify the relationship requires almost no knowledge of physics.

I have little doubt that your students will get significantly greater satisfaction out of the labs you outline, compared to the traditional cookbook follow-the-step-by-boring-step labs that low-lighted my undergraduate physics education. If students can discover on their own that such relationships exist (and, hopefully, what those relationships are), then you'll be helping to build better scientists AND better citizens.

The measure of what the students have learned is their ability to flat out state how A depends on B, and what would happen if one varies B. A "bonus" measurement would be on how close was the outcome based on what they expected before performing the experiment. It is always a tremendous lesson to realize that the result is different than what one had predicted. To me, this is THE part where we learn, i.e. when we're wrong. The balloon in the train part is all about this. This is how science progresses, and that experiment is an opportunity to show that.

Agreed. Prediction and discovering where we were wrong is indeed the part where we learn, and research exists to back this claim. See, e.g.:

Inventing to Prepare for Future Learning: The Hidden Efficiency of Encouraging Original Student Production in Statistics Instruction.
Daniel L. Schwartz & Taylor Martin. Cognition and Instruction. 22(2), 129–184, 2004.

I concur that, for example, the measure of what the students have learned is their ability to flat out state how A depends on B, and what would happen if one varies B. In my experience, however, a sizable fraction of instructors are unconvinced that they should endeavor to change they way they teach based solely on statements of personal anecdotes from others - as I'm certain you know better than most, this kind of thing takes a decent effort. It's one thing to tell a colleague that your efforts are paying off, but it's more to show them quantitatively by how much more your efforts are paying. This is all I meant by my statement of the importance of assessment.

I look forward to reading about your future success with these labs!

 

[Greg Bernhardt]

This paper has been transferred to Insights. Great Insights as usual ZapperZ!

 

[ZapperZ]

I thank Greg for reopening this old discussion thread, now that it is tied to an Insight article. I wanted to continue with this topic because of a recent paper that I read.

https://journals.aps.org/prper/pdf/10.1103/PhysRevPhysEducRes.13.010108

It is an interesting study. In it, the authors studied the effectiveness of a physics lab exercise that emphasizes on lab skills, on reinforcing physics concepts, or both. They then look at the evaluations of the students based on E-CLASS assessment.

They came up with a rather interesting observation:

By examining raw E-CLASS scores both overall and by item, we found that students in skills-focused courses showed more expertlike postinstruction responses and morevfavorable shifts than students in either concepts-focused or both-focused courses. This result was further supported by an analysis of covariance, which showed that course focus (skills, concepts, or both) was a significant predictor of students postinstruction E-CLASS performance even after adjusting for the variance associated with preinstruction score, student major, and student gender. Moreover, the ANCOVA demonstrated that the increase in score associated with skills-focused courses was larger for women than for men, and the difference was large enough to eliminate or even reverse the typical gender gap. Overall, our findings support the conclusion that students in courses that focus primarily on developing lab skills demonstrated greater success with respect to fostering expertlike beliefs about the nature and importance of experimental physics as well as their affect and confidence when doing physics experiments.

You'll notice that in the experiments that I have proposed, the emphasize is on such lab skills. Often, the experiments do not even state what physics concept is being tested or is applicable. I think that without making such an explicit connection to a physics concept, students, especially non-STEM students, might feel less intimidated by a physics class/lab. And yet, they will be learning about a systematic and analytical process on discovering correlations and causation between variables.

Zz.

 

[ZapperZ]

There is another interesting paper that will appear in Phys Rev PER. It studies the effectiveness of the traditional intro physics lab in the students understanding of the course material. It found no strong evidence that these traditional labs actually made any difference. The conclusion is quite clear:

Our results have demonstrated a broken link between intended learning goals and measures of student outcomes. Nine different lab courses, designed to reinforce student understanding of physics content from other areas of the course, have been shown to provide no measurable added value to course performance. This was true across calculus-based and algebra-based courses at three very diverse institutions. We hope these results will encourage instructors and departments to critically evaluate whether their lab courses are achieving their full potential.

If you read carefully, they are not advocating that we do away with labs completely.

We also note that “studio” physics courses (where labs, lectures, and recitation are co-mingled in the same space and instructors move fluidly between the three forms of instruction) have demonstrated significant conceptual learning gains compared to traditional instruction [7, 23, 24, 45]. It is impossible to separate the con tributions of the labs in this integrated context, but they may provide greater benefits when used in this way.
.
.
In line with many national calls [8–11], our results should strongly encourage institutions to consider alternative goals and pedagogies for labs, especially those for which labs are demonstrably and uniquely effective. There is much research demonstrating the effectiveness of lab-based pedagogies at developing skills such as evaluating data and models, dealing with uncertainty and variability in data, and designing experiments [46–51].

One need not completely discard introductory lab activities to begin to make improvement. Research has shown that even small elements of open-endedness in activities can improve student attitudes towards experimental physics [16]. Providing students with time, opportunity, and incentive to revise, troubleshoot, or explore by, for example, spreading a single lab experiment across multiple weeks may enable the desired skills focus [35, 46]. Shifting the emphasis of the lab activities towards the quality of students’ process rather than the product they obtain would be key to facilitating that development [35]. It is unclear, however, whether entirely open-ended project-based courses would achieve the desired goals, especially when scaled for typical introductory course enrollments. Indeed, history has suggested that this is not a sustainable framework [2].

As I've stated my in original goals, I do not see these intro physics lab as being an instrument to reinforce the physics concepts that the students learn in class. Rather, I see it as a means to get student to think of what they are observing, whether there are any correlations between two different quantities, and if there is, is there a causation connection. The last part requires some sort of an analytical evaluation of what they have seen, and might even involve mathematical description and modeling.

None of these requires that they know about the physics involved. In fact, none of these have to be on physics. The physics labs become a place where people learn about how we understand the behavior of the world that we observe, and how we know something will work the same way next time, i.e. reproducibility. This paper shows that our belief that intro physics labs provide measurable contribution to content understanding of students is clearly not there. The focus of these labs should be in another direction.

Zz.

 

[gleem]

I wish to call to your attention (if you haven't seen it) the effort from the University of Maryland to address issues in physics education which seems to have been an issue for over a century (PhysicsToday| May 2017). They include a discussion of the role of laboratory sessions (Physics by Intuition) and even to the extent of eliminating lectures altogether as such including workshop and studio suite structures. Hope it is of some value for your work.

 

[Mister T]

I urge all interested in these issues to read "100 Years of Attempts to Transform Physics Education" by Otero and Meltzer. It's on page 523 of the The Physics Teacher, Volume 54, Number 9, December 2016. As a long-time advocate of the types of reform being discussed in this thread, I found it very interesting to learn that these ideas have been around for more than a century.

By the way, the RealTime Physics curriculum is an excellent resource for the types of lab activities being discussed here in this thread. I've been using it for about 20 years now and have modified it repeatedly and extensively during those years.

 

[Dadface]

It is common for UK high school physics programmes to have a coursework element. One format which I particularly liked had four parts:

1. Design.

Students were set a question eg:
What factors affect the resistance of a wire?

Students were given time to research the question and asked to come up with predictions. They had to plan experiments they could do to test those predictions.

2.Experiment

Students carried out their planned experiments.

3. Analysis

Students wrote up their experiments and processed their results eg plotted graphs ,carried out calculations etc.

4.Evaluation

Students had to come up with conclusion(s), describe how they could make improvements to their experiments and come up with suggestions on how to extend the investigations.

That's it in a nutshell.

 

[symbolipoint]

A recent post made yesterday put this topic as very visible in the board which is why I found and read some of the topic. This is how I saw the OLD post made by Bystander; I liked it, and so I put my "LIKE" to his posting. Not really trying to read old, "dead" posts.