Climb a tower of flashcards that keeps handing you the very word you're about to forget.
An adaptive recall model tracks how likely you are to remember each card right now, and keeps serving the ones on the edge of forgetting. Answer correctly to climb the tower; miss and you lose a life. The pressure rises as floors stack up, so the words you're shakiest on come back exactly when they're hardest.
Cram Climb turns adaptive flashcard review into a tower you ascend one word at a time, focusing practice on weak cards.
A model tracking how likely you are to recall each card right now, serving the ones on the edge of forgetting, is spaced repetition with a recall-probability estimate rather than fixed boxes.
Targeting the edge of forgetting is the original refinement.
That threshold is where the research points. Reviewing material you still know well is nearly wasted effort, and reviewing what you have already lost is relearning from scratch — the useful moment is the narrow band in between, which is exactly what the model is estimating.
Cram Climb is an original, free browser game that turns adaptive flashcard review into a tower you ascend one word at a time. It is built in-house and runs in your browser.