Last week I had my first try at implementing Problem Based Learning (PBL) in physics. We were about to study Heat Energy and it seemed like a natural fit for presenting an authentic problem. I chose to make a scenario that was based on my previous work as a mechanical energy. Have a look below…
From what I understand, PBL should be based on authentic situations where the solution is non-obvious such that the students need to engage their meta-cognition. As well, the problem needs to build upon prior knowledge and hopefully it can be multi-disciplinary. I think that in these respects, my above problems works very nicely. Having used in the class, I would say that it okay, but not perfect..
I set aside two days in the library to work on the problem and I wasn’t sure what to expect. To help the kids with resources, I put together an information package on heat and pointed the students towards www.physicsclassroom.com. I would have liked to have more print resources available but heat energy and transfer is typically reserved for upper level physics texts and generally well above the reach of physics 11 students. During the first class I had to step back and try to wipe a big grin off of my face because I had all my students clearly engaged in the problem, exploring solutions and learning about heat. It was inspiring to see.
Time flew by during the first class, and there were a couple of groups that hadn’t progressed too far. I decided to go back to the library for another session. This worked out okay for the most part but if I were to do it again, I would maybe stay in the classroom for the second class, and just have the groups exchange ideas.
In terms of evaluation the effectiveness of the PBL, I’m not too sure yet. I followed up the two PBL classes with a class where we zoomed through some notes, along with some practice problems. All told we spent 3 classes on heat. In my mind, this is an example of depth vs. breadth. At other times I have done heat we spent more time on more sub-topics (phase changes). If time wasn’t an issue, I would have done a lab where the students try to measure the temperature of a piece of heated metal. But hey! There’s always next year.
I also wanted feedback from the students to see what they thought about the PBL process. Below are some quotes that best described their reflections.
“This activity did allow me to learn about the various aspects of heat energy. I think that I learnt it all effectively, as when we reviewed the information in class it felt like a review. However, I found that actually finding the information on the internet was difficult. For some of the topics, such as heat, there were web pages which were full of very complicated equations which we don’t need to know at our level. Finding all the information that was pertinent to our topic was difficult, and then actually trying to understand the information given was a whole new ball game… It was quite nice not to be sitting in a classroom for a day, but I think that next time perhaps only one day trying to scour web pages for information, and perhaps the second day that we originally spent in the lab we could instead use in the classroom pooling all our findings.”
“… Which shows that we are not only learnt more about physics, but what good sources are and where to look for information. I found this project difficult because at first we were not given a lot to work off of, but after the help it became easier. All in all, I enjoyed having a self guided learning lab with just a bit of guidance. I liked having a chance to acquire the manual and mental skills associated with physics through a hands on experience. Any subject cannot simply be transmitted through words from a teacher. Lastly, I liked having to solve someone’s problem that seemed realistic because that way I could see more of a point to it as it relates to life.”
“Overall, I found this problem-based environment is a very useful tool in learning more about physics. It does not let us merely solve questions by having numbers in a simple problem, but rather, it allows us to come in contact with real-life situations, in this case problems in industry physics, and find solutions from different aspects. I believe that real physics learning should be like this, rather than aiming to achieve a one-and-only correct answer like what we do on normal tests. Therefore, I think we should have more problem-based experiments in future learning.”
It seems to me that the PBL was a big success. Many students said that the task was interesting, fun, engaging and seemed like real-life. A common complaint was that it was very difficult at first and confusing. However, I think this is okay and that the students did have appropriate scaffolding prior to the problem, having learnt about conservation of energy, temperature and heat previously. Some students thought that two classes was too long, and this definitely needs to be considered for next time. Of course there were a few students that prefer notes and being told what they should know, but not everyone can be pleased all the time.
