Radioactive Decay Model

This exhibit models radioactive decay of nuclei and fundamental particles with wooden cubes. There are 100+ hardwood cubes each with one side painted red. These cubes are placed into a wicker bowl and tossed onto a table. The cubes that land red side up are removed and placed into one column at the bottom left edge of the table. The smaller number of remaining cubes are then placed into the basket and tossed again. The cubes that land with their red side up are removed again. The process continues until there are no cubes left.
The exhibit teaches about half-life; half of all the remaining cubes "decay" after every 3 tosses. The decreasing columns of cubes show an exponential decay in height. This exponential decay results from the constant 1 in 6 probability that each cube will decay on each throw.
The random fluctuations in the height of each pile are also visible in the non-smooth profile of a curve connecting the heights of the columns of cubes.
The crash of the cubes from the basket is such an interesting sound that young children spend time throwing the cubes from the basket and arranging them in piles.
The "decayed" blocks form an exponential pattern of piles.