GENIUS!!! SCUM-PROOF your glass shower doors by using Water repellent products! Rain-X ($5 at auto parts stores!) Causes water and soap to bead off glass and not scum up for 6 months! - this is GENIUS.
Glitter Germs! Put it on the teacher's hands, and then have everyone, including the teacher, shake hands with everyone. Notice how the "germs" spread! A good little reminder for the typical "wash your hands" talk when flu season is in full swing.