From fractions to Spivak calculus.
Principia teaches mathematics the way it actually works — unified, visual, and grounded in the why behind every formula. 6th grade through college. Free to start.
Free forever for Tiers 1–2 · No account required to start
8 tiers · 60+ concepts · 6th grade through Spivak
How it teaches
Every concept starts with a plain-English explanation and a real-world connection — before a single symbol appears. The formula follows understanding, not the other way around.
Every concept has an animated diagram that responds to what's being taught — not a static image you ignore.
Worked problems where each step is hidden until you're ready. You control the pace.
Pythagorean theorem connects to trig identities connects to calculus derivatives. Every module shows where its idea lives in the larger structure of mathematics.
Mathematics is unified
Principia shows how algebra lives in geometry, how the Pythagorean theorem is secretly a trig identity, and how a parabola and a derivative are the same conversation.
"Mathematics is not a collection of formulas to memorize — it is a way of thinking. Principia teaches the thinking."
Built for every student, from first fractions to epsilon-delta proofs.
Simple pricing
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