This video demonstrates the stretching of an ordinary elastic band using 100g masses. The masses are first loaded on to the band, and then removed one at a time. A close up on the masses allows measurements to be taken from which the extension can be calculated and a graph plotted. Close observation also reveals that the band continues to extend after the masses have been applied, and remains slightly stretched after their removal, resulting in a hysteresis curve.
The main points of the video are:
Non linear (plastic) behaviour (does not obey Hooke's law)
Creep
Hysteresis curve.