Download high quality here. Here's the pilot but I need to modify the prompt somewhat. Every math teacher reading this likely sees the mathematical potential in this image. Most could come up with a question right now like, "If this is a four-number combination lock, then how many combinations will you have to try to break in?"
Lately in these threads I get lists of those questions, which is great, but questions don't constitute a lesson plan. So consider this the new prompt: what is the lesson plan? what will the students do? what is the best plan to provoke sustained, rigorous inquiry?
Let's push this forward.
BTW: My lesson plan.