On the bench · not built yet

Circle Theorem Explorer

Drag points around circles and watch inscribed angles, chords and tangents keep their relationships.

Nearby on the shelf

Move a shape onto its twin with the fewest transformations; prove congruence by mapping.

Drag statements and reasons into a proof that holds up; a compass-and-straightedge sandbox handles constructions.

Measure a flagpole with its shadow and a meter stick using similar triangles, then check with the real height.