Marshall Memory vs Proof Fidget

Marshall Memory is a free app that helps you remember important stuff – an evocative quote, a favorite poem, the punchline of a joke, helpful statistics and acronyms, vocabulary in another language, perhaps the names of a friend's children. Enter words (or an image) and the app will prompt you by notification or e-mail at intervals you choose, using two techniques from cognitive science – retrieval and spaced review – to commit the item to long-term memory. Download Marshall Memory now and start building your memory muscles!

ProofFidget is a puzzle-driven way to learn the feel of doing math: not by memorizing procedures, but by making correct moves, one step at a time, until a proof truly holds together. Each puzzle gives you a clear goal and a partially-complete derivation. You spin the wheel to choose your next move, then commit to a step and watch the proof line up. If you’re right, you progress; if you’re wrong, you learn quickly why it didn’t fit. The result is a tight feedback loop that makes abstract ideas concrete and surprisingly fun. You’ll work across a growing set of subjects, including: Logic and proof techniques: build confidence with implication, contradiction, and structured reasoning. Algebra: make valid transformations while keeping equations balanced, supported by visual “balance scale” diagrams. Number theory: practice modular arithmetic, divisibility, and gcd-style reasoning with intuitive visuals. Geometry and beyond: use diagrams to ground symbolic steps in something you can see. ProofFidget is designed for short, satisfying sessions, but it also rewards deeper play: you start noticing patterns, choosing steps for the right reasons, and developing proof instincts that transfer to real coursework and problem-solving. If you’ve ever thought “I understand the formula, but I don’t understand why,” ProofFidget is built for that moment.