I wrote earlier this year about my difficulties with equation reference sheets. Students fall into the habit of using them like a menu rather than a set of tools.

Yesterday I had the great experience of trying a revised approach. The idea is to rely more on memorization, but only so far as keeping close definitions that are crucial to understanding.

A student asked during a quiz for a formula for electric field. I said I wasn't going to provide one, so I pushed further to find out why this student needed it.

The student asked for the relationship between electric field, charge, and force. I provided this:

The student subsequently nodded and told me what went where. I then stepped away, keeping the post-it note with me.

This was an application of the definition of electric field, not Coulomb's law, and the student either knew this, or guessed. In either case, it was enough to enable the student to then solve the problem completely.

I don't know yet what this means, but it seems like a step in the right direction. I wonder if providing a reference sheet with random elements erased might be enough of a skeleton to encourage the students to know how to fill in the blanks, but wouldn't allow the sort of hunting that students often do in a problem solving situation.

It has been a nice start to the year, folks. Here's to a great school year for all of you.