GeometryForge

Geometry decomposes neatly into named theorems (right-triangle relations, inscribed-angle, transversals) and named construction patterns — every character embodies one foundational geometric idea, no real historical figures.

Level 1

Build & reason — hands-on geometry surfaces

Six ways to do geometry, rebuilt for the browser — the same skills as the iOS app, plus two you can only do here.

Property-Chain Reasoning ✨ new Build a proof yourself: pick the deduction that follows next — vertical angles, triangle sums, parallel lines, exterior angles — until you reach the conclusion. Every wrong pick explains why. Fill the Point ✨ new Discover which shapes tile: place polygon corners into a vertex and watch them fill toward exactly 360° — no gap, no overlap. Six triangles? Three hexagons? A square and two octagons? Geometry Studio Make an angle to a target with a live protractor, build a polygon to a given interior-angle sum, and set complementary & supplementary pairs. Transformation Lab Slide, flip, turn, and scale shapes on a coordinate grid: name the transformation, tap where a vertex lands, and find a shape’s line of symmetry. Geoboard Stretch a rubber band around the pegs to enclose an exact area — and watch Pick’s Theorem balance as you drag. Concept practice 17 short question rounds, from points & angles up to advanced synthesis — pick one below.

Practice the concepts

17 kits from an intro to points & angles up to advanced synthesis — a short round of questions with a hint whenever you get stuck. Your progress stays on this device.

Meet the cast — the characters who teach this

Each one stands for an idea you’ll practice. Tap a character to read their illustrated story and hear their audio drama.

Explore all the stories →

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