Geometry games &amp; apps

Solstice Courtyard

Walk a geometric year through four stone season gates and measure axial tilt, ideal daylight and solar-noon shadows.

Elin351

Snell Plumb Facet Lantern

Seat two declared index plaques, tilt one local facet, and tension exact ideal Snell-law ray threads through four slope controls.

Elin60

Registration Screen Atelier

Overlay measured ideal line gratings and pull proofs of their geometric moiré spacing.

Elin50

Terminator Shadow Meridian Drum

Set a frozen teaching instant, rotate a declared Sun-vector cam, and classify six synthetic spherical cells while real data stays blocked.

Elin40

Halo Cold Chamber

Rotate a 3D hexagonal ice crystal, catch refracted rays, resolve the spectral minimum, and build an honest atmospheric halo ensemble.

Elan30

Throat Ring Embedding Foundry

Forge and gauge one exact Morris–Thorne/Ellis equatorial spatial embedding profile.

Context Disc Measuring Balcony

Seat, surround, and caliper an exact Ebbinghaus context-size geometry fixture.

Mirror Wedge Specimen Tunnel

Insert an asymmetric point into a 45-degree mirror wedge, pin its exact D4 orbit, and expose fold-count and physical-optics boundaries.

Geocentric Sighting Rostrum

Turn two synthetic circular orbits and pin an apparent retrograde sightline sequence.

Needle-Shear Parallax Atrium

Rotate an exact unit needle, shear finite direction sails and keep pixels, area, containment and motion mathematically separate.

Sightline Thread Cabinet

Shift a synthetic observer and reveal how one angular pattern can conceal unequal stellar depths.

Curvarium — A Museum of Living Curves

An interactive gallery where mathematics becomes art. Ten living exhibits — roses, Lissajous knots, the golden-angle sunflower, Fourier's square, Ulam's prime spiral and more — each drawn live, each with sliders to bend the math and a Morph tour that animates the whole family of curves. For students, teachers, and anyone who suspects equations might be beautiful.

Elin333

Topiary Trim

Swipe-slice overgrown hedges into elegant Art Nouveau topiary silhouettes across four gardens, then grow a persistent trophy gallery.

Elin40

Chromatic Reflection Drum

Hinge a 1968 optical drum, place a chiral acetate seed, and develop nine exact reflection-group contact sheets.

Elan20

Shear-Line Locksmith Bench

Operate a monumental museum cutaway through twelve commissions, diagnose exact pin-stack blockers, and turn only when five fictional joints share one boundary.

Elan20

Fold Kinematics Conservatory

Operate eight tactile paper-geometry instruments, fold one exact degree-4 vertex in 3D, and sort necessary checks from stronger theorems.

Elan20

Antisolar Rain-Curtain Stage

Align a constant-index primary-rainbow ray and move its observer-centred cone without inventing a world-fixed foot.

Trisector Tailor's Table

Pin one scalene fixture, intersect adjacent angle trisectors, and gauge its inner Morley seam.

Shear-Line Locksmith Bench

Cut a supplied fictional key, inspect five pin-stack boundaries, and turn a teaching plug only when every chamber reaches one shear line.

Saddle-Tile Letterpress

Operate a curved mathematical press to measure Poincaré distance, classify regular inlays, and discover why the disk rim is unreachable.

Pulse-Lighthouse Drum

Align a synthetic pulsar lighthouse, register genuine beam crossings, and separate a rounded teaching period from catalogue evidence.

Angle-Doubling Kiln

Shape polar clay, square its radius, double its angle, and fire seven exact complex-number receipts.

Hexagonal Light Gauge

Seat, rotate, and sight ideal ice prisms to uncover the minimum-deviation geometry behind the approximately 22° halo.

Foldline Proof Rack

Test Kawasaki and Maekawa local flat-foldability conditions on one suspended mathematical sheet, then confront the global-proof boundary.