How things work college course/Breaking broomstick demonstration

This is not really a lab but a demonstration. I am looking for ways to make it more educational. These are ideas I have jotted down.

Waves that travel at the same speed for all wavelengths

 * Light in vacuum
 * Sound
 * Transverse and longitudinal waves on a string
 * Shallow water waves (approximately)

Waves that travel at a speed that depends on wavelength

 * Bending waves. [[file:Bending_Wave.gif|thumb]]
 * AJP
 * Youtube demonstration at Wright State showing how things can go wrong
 * Slow motion youtube demonstration
 * Whistler waves
 * Schrodinger waves
 * Light waves in materials
 * Explains chromatic abberation
 * Used to calculate how much plasma is between the stars