ProbSim

Prob Sim was a Macintosh (Classic) program from the 1990s with accompanying instructional activities designed for teaching probability via simulations in grades 6-13.
To model a probabilistic situation, you:
- construct a "Mixer" containing the elementary events of interest;
- sample from the Mixer after specifying replacement options, sample size, and number of repetitions; and
- search for or count specified events of interest in that and subsequent samples.

The program made the last step especially easy. Once analyzes had been conducted on one sample, you could press a button to see the results of the same analyses performed on a new random sample.

Prob Sim was especially useful for mathematics teachers striving to teach students probability in line with recommendations offered by the National Council of Teachers of Mathematics in their Principles and Standards for School Mathematics.