I'm a fan of...
This simple activity meets the needs of students who sit in classrooms without air conditioning. Create a fan with two simple pieces- wooden handle and stock card. I love that the fan's simple technology also allows a school to promote... anything! Clubs, sports, a course like Modern World Studies. It is a great way to promote student artists or students running for election. It would also be useful to math teachers, they could print formulas or routine equations, English teachers- poetry, librarians- favorite books... Students could decorate them on their own or vote for the best fan... I love it's simplicity.