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The Praxis, the FMCE, and the Intro Course

September 14, 2011

I began my independent study course for future physics teachers by asking students to collect information about what was covered on the Praxis. I then asked students to rank where they felt most/least confident. Collectively, the areas of E&M and Optics/Waves were least confident and Mechanics was the most confident.   We decided they would start doing independent study with statics, including Coulombs law, insulators, conductors, induced charge, electric fields, electric potentials, electric flux, electric potential energy. I sent them home to find any intro physics textbooks, and to begin reading and working on problems. They had 10 days to read and to begin working on problems, before we’d meet to work through problems or concepts they were struggling with.

In the mean time, I had them come in and we all took the Force and Motion Concept Evaluation (FMCE) quietly in a room together. In my mind, this would be an external check on their self-assessed confidence with mechanics. Not surprising, the students struggled. While their was some variance on their answers to particular questions, the students as a whole answered many of the questions identically wrong. In places, whole pages would be wrong for every student, with the students sharing the exact same wrong answer on more than half. (Aside: They weren’t copying, if that’s what you are thinking). This isn’t surprising as many of the wrong answers aren’t random, they indicate very specific and common misunderstandings, difficulties, or misconceptions. In addition, these students have been through the same courses, where I believe many of these difficulties are not being resolved.

The big struggles they have are:

  • Indicating a force in the direction of velocity; and the need for force to maintain velocity
  • Indicating the need for an increasing force to cause speeding up (but not slowing down)
  • Confusing velocity with acceleration
  • Recognizing Newton’s 3rd law as holding when acceleration is occurring
If you know much about the FMCE, you should know that if you are struggling in these four areas, it’s easy to walk away from this test answering a vast majority of the questions wrong. For the most part, they did well with velocity vs. time graphs but did poorly on any questions relating to Newton’s 2nd law, whether it be force graphs, acceleration graphs, or indicating the direction of force or acceleration.

A bit of Evidence to Support my Instructional Instinct

I have written in the past month about my uneasiness with the introductory physics course I help to teach. My instructional instinct was that many of the problems were not targeted properly for student learning and that there was too much emphasis on plug-n-chug routines rather than on understanding concepts.  I’m not saying that giving the FMCE to a handful of students a year or more  after the intro sequence proves anything. Rather, to me it indicates that my uneasiness has to no reason to subside. These students all did well in this intro course, and the consistency of their struggles is a possible indicator of the legitimacy of my gut feelings.

How to turn this into a learning opportunity?

One good thing is that all the students struggled. It’s not as if we have a situation where some students bombed it and others aced it. Everyone struggled and they are struggling in nearly identical ways. A part of me is excited that we have some meaningful learning to do, and that we are all “in it” together. The question for me right now is, “How do I best use this for learning?” We certainly can’t spend the semester relearning mechanics.

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