The Noun Project sponsored an iconathon to create and compile a collection of little drawings to represent educational topics. Many icons were designed, two of which caught my eye.

Games for Learning, Problem-Based Learning

Since I'm trying to teach folks how to play puzzlehunt games, I want another icon, one for Game-Based Problems for Learning Problem-Based Games. C'mon designers, get on it. OK, I don't really want that icon. I'd rather imagine it.