ProofQuest

Learn to prove things the way mathematicians do — one justified step at a time. Meet the guides who each teach one proof technique, then build proofs yourself.

Level 1

Build a proof

Two hands-on reasoning surfaces — the same skills as the iOS app, rebuilt for the browser.

Proof Builder Tap the proof steps in the right order so each one follows from the last. · 16 proofs Counterexample Hunt Find the one case that disproves a claim that looks true. · 6 puzzles

More ways to reason

New proof modalities built for the web first — each one a different way mathematicians justify a claim.

Construction Proof · new Recreate a compass-and-straightedge construction step by step, then see why it works. Two-Column Proof · new Fill in the reason that justifies each statement — the classic school-geometry format. Knights & Knaves · new Knights tell the truth, knaves lie. From what each says, deduce who is which. Induction Dominoes · new Sort the base case, hypothesis, and step — then topple the whole chain.

Practice the concepts

16 kits from logical-thinking basics up to advanced synthesis — a short round of questions with a hint whenever you get stuck. Your progress stays on this device.

Kit 1: Logical Thinking Basics Logic & Reasoning · grades 4-5 · 25 questions Kit 2: Patterns and Conjectures Logic & Reasoning · grades 4-5 · 25 questions Kit 3: Deductive Reasoning Direct Proof · grades 5-6 · 25 questions Kit 4: Inductive Reasoning Induction · grades 5-6 · 25 questions Kit 5: Mathematical Arguments Direct Proof · grades 5-6 · 25 questions Kit 6: Visual and Geometric Proofs Logic & Reasoning · grades 6-7 · 25 questions Kit 7: Famous Problems and Puzzles Logic & Reasoning · grades 6-7 · 25 questions Kit 8: Proof Techniques Logic & Reasoning · grades 7-8 · 25 questions Kit 9: Direct Proof Methods Direct Proof · grades 7-8 · 25 questions Kit 10: Proof by Contradiction Proof by Contradiction · grades 7-8 · 25 questions Kit 11: Counterexamples & Disproof Counterexamples · grades 6-8 · 25 questions Kit 12: Mathematical Induction Intro Induction · grades 7-8 · 25 questions Kit 13: Cross-Topic Connections Logic & Reasoning · grades 5-6 · 25 questions Kit 14: Real-World Applications Logic & Reasoning · grades 6-7 · 25 questions Kit 15: Misconceptions & Reasoning Logic & Reasoning · grades 6-7 · 25 questions Kit 16: Advanced Synthesis Logic & Reasoning · grades 7-8 · 25 questions
ProofQuest mascot

Meet the cast — the characters who teach this

Each one stands for an idea you’ll practice. Tap a character to read their illustrated story and hear their audio drama.

Explore all the stories →

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