COSMO · Interactive experiments

Try it.
Explain it.

Change one thing. Notice what happens. Build an explanation with someone else. These eight experiments connect directly to the teaching decks.

Bring a question and a partner.

Make a prediction before you touch a control. Test it, compare evidence, and switch who leads.

Start with backpropagation

Watch the chain rule do its work.

Follow a prediction forward and a gradient backward. Then decide which way the weight should move.

Follow values forward, sensitivities backward, and then make one weight update.

Move a weight along a loss curve and investigate what the learning rate changes.

Rotate a projection axis and measure how much variation survives.

Move a query vector and compare neighbors under distance and cosine similarity.

Build a network, predict a one-stroke route, and trade puzzles with a partner.

Build a remainder history one power at a time, then predict a huge exponent.

Remove squares, try covering the board, and look for a quantity every placement preserves.

Rotate a secant, record two distances, and look for a relationship that survives.