Spaced Repetition If one thinks of our brain as a muscle—each repetition is a "flex" of that muscle. Over a period of time, you are slowly pushing the muscle steadily with a more challenging task . One can also gradually increase the intervals between repetitions, once the skill is learned. The practice of mugging formulas, which we detested in school, was a necessity. One will not derive the formula every time to work on a problem. After a point, it becomes second nature to use the right formula for a problem. Same with our kids. Teaching by small incremental steps and practicing each step frequently until the knowledge becomes automatic. Be it recall, communication, skills, practical applications; spac...