Thomas Bretl

ProbSim

ProbSim is a probability experiment simulator. You can flip coins, roll dice, spin spinners, and draw marbles from urns. Predict the probability of a ...

Algernon

Using just three simple commands (forward, left, and right ), guide the mouse Algernon through a maze to reach a piece of cheese. This app is especial...

GeoFit

Based on Donna Bretl's wood "Bretl Blocks" puzzles, GeoFit challenges you to fit small squares, diamonds, triangles, and trapezoids into square, hexag...

SquArray

Investigate 3x3and 4x4 arrays of both numbers and shapes. Solve magic squares and create beautiful geometric patterns that change in surprising ways w...