Why I like this problem: There several different levels allowing students to choose the ones they are comfortable working on, and working their way up in difficulty. The problems seem straight forward at first, until students realize that they need to think outside the box to obtain certain missing measurements.
Observations from class: Students had a difficult time initially figuring out how to get the missing measures, but did well once they were able to get past this struggle.
Follow-up questions I asked:
1. Is the route you used the most efficient one? Could you have gotten to the answer in less steps?
2. Do you need to use all of the rectangles to get to the answer?
Required skills / content: Figuring out patterns, counting.