The original games ran on Flash and Java applets, which no longer work in modern browsers. These four have been rebuilt from scratch in HTML5 — they run right here, on any device, no plug-ins.
Pendulum Lab
A modern rebuild of the old Pendulum and Spring Pendulum Java applets. Watch simple harmonic motion, change gravity and length, and see the period respond in real time.
Tip: drag the bob to a new starting angle, then release.
Times Table Attack
Sixty seconds. How many can you get? Pick the operations, hit Start, and type answers — press Enter to lock each one in.
Unit Circle Explorer
The interactive rebuild of the old trig pages. Drag the point around the circle to see how sine, cosine and tangent are born — or switch to Quiz mode and test yourself.
Function Sniper
Three targets appear on the grid. Tune the equation of a line or a parabola until the curve passes through every one of them. Fewer moves, bigger score.