Tell us about yourself!
Are you sure about the diode between 5V and GND? It looks like you are shorting out your Arduino in this way (and could damage it).
Physics Demos for High School Teachers Made by Freshman Students From Delft University of Technology
Natuurkunde Demonstraties Voor Middelbare Scholen, Gemaakt Door Eerste Jaar TU Delft Studenten
Wave Pendulum (dutch Instructable)
Fluidised Sand Bed Demo
How to make a Bottle Prison
The Maven Box: an Arduino Controller for Software Developers
DVD Stash Box!
How to build a Nintendo arcade