The best way to learn geometry interactively

Interactive problem solving that's effective and fun. Get hands-on with angle axioms, perimeter and area calculation strategies, coordinate geometry, 3D geometry, and more.

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Courses covered

Measurement

Measurement

  • Angle Axioms
  • Measuring Areas
  • Parallel and Perpendicular Lines
  • Perimeter
  • Similarity
  • Surface Area
  • The Pythagorean Theorem
  • Three-Dimensional Figures
  • Volume
Beautiful Geometry

Beautiful Geometry

  • Convexity and Concavity
  • Deconstructing Origami
  • Fisk's Coloring Proof
  • Fractals
  • Lattice Polygons
  • Packing Puzzles
  • Pick's Theorem
  • Polyominoes
  • Reptiles
  • Tessellations
  • The Art Gallery Problem
  • Triangulation
Geometry I

Geometry I

  • Angle Axioms
  • Angle Hunting Shortcuts
  • Composite Area
  • Complementary Areas
  • Curry's Paradox
  • Invariant Areas
  • Polygon Angles
  • Regular Polygons
  • Stellations
  • The Triangle Inequality
  • Triangle Congruence
  • Triangle Similarity
Geometry II

Geometry II

  • Centroid
  • Circumcenter
  • Cyclic Quadrilateral Theorem
  • Euler's Line
  • Incenter
  • Inscribed Angles
  • Intersecting Chord Theorem
  • Intersecting Secants Theorem
  • Intersecting Tangent Theorem
  • Orthocenter
  • Power of a Point Theorem

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Courses in Foundational Math

  • Solving Equations
  • Measurement
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  • Geometry I
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