Every time you retrieve information from memory - before seeing the answer - you strengthen that memory trace far more than reading it again. This is called the testing effect. Roediger & Karpicke (2006) showed students who were tested retained 50% more after a week than students who re-studied the same material.

Fill-in-the-blank outperforms multiple choice because your brain has to construct the answer rather than identify it. This is the generation effect - the mental effort of producing a response creates a deeper, more durable memory trace. That's why we use more fill-in-the-blank than multiple choice.

When you mark a card "Again," it re-enters your queue just a few cards ahead. This is a simplified form of spaced repetition, which exploits the spacing effect: reviewing material at the moment you're about to forget it produces stronger long-term retention than reviewing it when it's still fresh.

Interleaving flashcards, fill-in-the-blank, and multiple choice within a session feels harder than doing all of one type at once - and that difficulty is the point. Desirable difficulty research shows that varied practice produces better long-term retention and transfer, even though it feels less efficient in the moment.

A deck completed across three sessions is more effective than the same deck completed in one sitting. The app tracks your points across the whole semester so that studying is worthwhile every week - not just before an exam. Distributed practice is one of the highest-impact, lowest-effort learning strategies known.

You earn points for completing decks, not for getting answers right. This is intentional. Performance-based rewards shift focus to the score and away from learning. Process-based rewards encourage engagement with difficult material without the anxiety of being graded on each response.