First, some background. I’ve historically been a direct instruction-heavy teacher. I’m trying to shift away from that so students are more active in their learning. With an activity like this, I’ve found that the “debriefing” time at the end is crucial (though I haven’t mastered it yet), otherwise my students will often miss the point of a lesson. So in a general sense, those “notice” questions are designed to grease the skids for our debriefing time.

In this particular activity, my goal was for students to observe/notice/learn that scaling the sides of a triangle by a factor of n does not affect the angle measures, and that scaling the side length by n multiples the area by n^2.

Additional thoughts? Are there salvageable parts to the activity? Things to rewrite or throw out? Or back to the drawing board?