Student created math questions
At my public library job, I've been encouraging students to invent their own math questions using Number Banner 1. One very bright 4th grade student, Crosby, invented "The Crosby Question," which is best suited for high school students -- or advanced middle school students. The Crosby Question is -- "Find three numbers on the banner, whose sum adds up to 200. None of the numbers can be round numbers." So -- a possible answer to this question might be 97 + 54 + 49.
Kudos to Crosby for his inventiveness. I have a hunch he'll be invented other math questions, too.
The reason we encourage students to invent their own math questions is that gives them a greater sense of agency -- of power. It can be fun for them (or anyone else) to stand around and watch someone try to answer your question.