"Rainbow at the End of the Pot of Gold" Run out and grab a few buckets (craft store or dollar store), some gold spray paint if you can't find gold buckets. Add coloring pages, rainbow of crayons and you have a great treat for when the kids get home!
Celebrate the grad! Make clear balloons more festive (and less boring) with confetti! Sprinkle small amounts of tissue-paper confetti through the mouth of the thing, then blow it up and shake to dispense it around.