Generate any desired likelihood.
This is an educational toy, gambling device, and simulation aid. A small box has a push button, a light, and a knob marked from 0 to 100. When the knob is set at some probability, such as 70%, and the button is pressed, there is exactly a 70% probability that the light will come on.
This could be an added function for a pocket calculator. The user could enter a two digit number, press a key, and see a sign with the probability entered.
A child who plays with this for a few hours will learn to relate probabilities to their numeric values. Simulation and war games could be played using the pocket randomizer to generate the desired liklihoods.