You hot glue crayons around a half pint size canning jar. Tie on a ribbon and spray paint the lid black to represent a chalkboard. Glue on a school themed decoration for the top and fill with something sweet. (M's, Skittles, Hershey's Kisses, granola, jelly beans or whatever you like).
I made these vases for end of year teacher gifts last year. I bought simple straight vases for a dollar at the dollar store. Instead of just wrapping the pencil crayons with a ribbon, I hot glued them right on the vases. One I did in rainbow colours and one I did in random colours. They were a big hit, with lots of oooh and aaahs!