“Touching” mathematical facts is fascinating and rewarding. An electronic encyclopaedia of models will collect all the known ideas. It is possible to build many of the presented models yourself.

More models — in the Russian version

Models

Pythagorean theorem2

Triangle, polygons1

Areas and dissections of shapes3

Circle2

Conic sections5

Conic sections: parabola4

Conic sections: hyperbola2

Conic sections: ellipse1

Polyhedra2

Volumes1

Number theory4

Formula geometry1

Arithmetic and geometric progressions1

Trigonometry1

Geometric transformations2

Kaleidoscopes3

Non-Euclidean geometry1