THE PHYSICS CURRICULUM, OPEN TO EVERYONE

Learn physics the way it's actually understood — by doing it.

Twenty-four courses covering the worldwide canon, from kinematics to quantum mechanics. Every lesson pairs careful reading with problems and a live simulation.

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24 courses ·1,900+ lessons ·140 labs ·no ads, ever
LAB 2.4 · PROJECTILE MOTION live
θ = 52° v₀ = 24 m/s R = 57.7 m

Six tracks. One canon.

Full catalog →
TRACK 0 · 2 COURSES
Foundations
The toolkit: math for physics, measurement, estimation.
TRACK 1 · 4 COURSES
Classical Mechanics
How things move, and why.
TRACK 2 · 5 COURSES
Electromagnetism
Fields, charges, circuits — and light, eventually.
TRACK 3 · 4 COURSES
Thermo & Statistical Mechanics
Heat, entropy, and the physics of many things at once.
TRACK 4 · 4 COURSES
Waves & Optics
Everything that oscillates, interferes, and diffracts.
TRACK 5 · 5 COURSES
Modern Physics
The twentieth century's two revolutions, and what followed.

Read. Solve. Simulate.

01 — READ
Lessons that derive, not recite
Short readings with every equation motivated, plus a 6-minute video per lesson.
02 — SOLVE
Problems with real feedback
Graded hints, unit-aware answers, and worked solutions that show the reasoning.
03 — SIMULATE
Labs you can break
Every unit ends in a sandboxed simulation. Change gravity. See what happens.
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