Spaced review means returning to a topic on different days instead of doing all the practice in one sitting. The useful interval depends on how difficult the material is and how soon you need it. A calendar is a starting point, not a guarantee of retention. Choose a small topic and review it tomorrow, a few days later, and again the following week. Begin each review by answering a question without notes. Check the answer and move a difficult item to an earlier review. If an item is easy, explain it with a new example before extending the interval. For a vocabulary list, use each word in a sentence rather than only rereading its definition. For mathematics, solve a fresh problem that uses the same idea. Keep the session short enough to complete consistently. Try it today: Create three review appointments for one topic. At each appointment, record what you recalled correctly and what needs another attempt.