For live classroom demonstrations there are a number of devices that have been used to simulate waves. Some are based upon a design produced by E. S. Ritchie & Sons1 and consist of rods and cams that are activated by turning a crank.2,3 These devices show what transverse and longitudinal waves look like, but they do not allow for the free manipulation of wave parameters and observations of the changes that take place. A simple device can be constructed using elastic bands and straws4 to demonstrate properties of transverse waves.
Trikosko, Walter L. and Callaway, Thomas O., "Apparatus for demonstrating longitudinal wave pulses" (2011). Faculty Publications. 6.