To get students thinking again about technical justifications for curve sketching today, I started with this warm up gallery walk.
1) Students did a silent, individual gallery walk to critique justifications (some close, some very off, maybe even some right!?). They left a post it under each one with their feedback on how to make it better.
2) Next, I grouped students and had them each work on one particular justification. Students read through the feedback and sorted it, using it to generate a new and improved justification.
3) Each group presented the feedback they'd seen on their problem and their new and improved justification to the class. This gave us an opportunity to talk as a class about what could be improved and to examine some common issues.
After that, we did a released AP problem that required multiple justifications and I saw a huge difference in the precision of their language. It was a good jump back into more extensive mathematical writing. It could also be applied pretty easily to EVT, MVT, and IVT justifications, among other things!