Some Observations
It is approximately halfway through the semester and I have some observations. I have spent a lot of time in class trying to emphasize what is important and drop the rest on the side of the road before I come into work. I would like to say that these statements aren’t blanket statements. Many of my students may not fit into any of these categories and just because they do doesn’t mean there is something wrong with them. Here are my observations.
Many students still can’t recall Newton’s Laws.
Newton’s Laws are ridiculously important. If the students can’t even recall Newton’s Laws than how can we expect them to understand anything else we talk about in this course? At this point in the semester the students should at least be able to list them to me when I ask and many can’t. Perhaps I haven’t been emphasizing how important Newton’s Laws are to force and motion (maybe it would be more clear to them if we had started the semester teaching Newton’s Laws instead of kinematics).
Many students have begun to not take the activities as seriously as they did at the beginning of the semester.
This is probably due to several reasons and I’ll mention one of them. The grading scheme has consisted more so on participation than on accuracy of the written statements. This is because I think that marking students down for writing the wrong answers on the page is not a viable solution that helps the student to learn.
The students are having a hard time seeing how the activities they are doing is helping them.
I have blogged before about how the undergraduate curriculum needs to include objectives that the students actually care about. Objectives that their future employers actually care bout. No one will ever care if these students can find the forces on a object resting on an incline plane. This is not a calculus based course. Physics majors don’t take this course. So why are we teaching them like they are physics majors? Why do we expect them to care? Perhaps we should create a list of standards for the course (thank you Andy) which are also motivated. Every standard will have next to it a reason why someone other than a physicist would care if the student can perform the skill or demonstrate mastery.
These are some things to think about between now and next semester. I suppose I could always just talk about everything through the lens of Battlestar Galactica.
John,
I’m curious, how do you guys teach newton’s laws?
For a very progressive classroom style it is surprisingly traditional curriculum wise. We start with kinematics, position -> velocity -> acceleration. By the time we get to acceleration students are struggling with the abstract nature of the concept. When you introduce something as “the change in the change in” something most students are going to bork. Then we do Newton’s first law -> 2nd Law -> 3rd Law. In my opinion it’s really quite backwards. What if we started with Newton’s 3rd law? It is really what is most important and the concept of equal and opposite pervades the course (I’m looking at you momentum and energy). If we started with Newton’s 3rd and 2nd we wouldn’t even have to introduce acceleration. Just talk about force as “something that causes change in motion”. I stress this idea often. Force causes change in motion. Maybe students don’t understand what I mean by “change in”. Maybe I should break it down even further.
John,
Yeah, your statement of N2 is more along the lines of what I try for in my classes. I’m going to post something on a new twist on N3 I’ve started to think is pretty valuable, which comes from emphasizing interactions.