Spaced repetition is one of the strongest evidence-based methods in learning science. Here is how to apply it correctly.
Key Takeaways
Reviewing right before forgetting improves retention efficiency.
Intervals should grow over time as confidence increases.
Short, frequent sessions outperform occasional long sessions.
Why timing matters
Memory strengthens when recall happens with moderate difficulty. If review is too easy, gains are minimal. If it is too late, relearning cost rises sharply.
Spaced systems aim for the middle zone where effort is real but success is still likely.
Operational rule of thumb
Early reviews can happen within one day, then after three days, one week, and two weeks. Intervals should expand as mastery grows.
When a learner misses an item, the interval should shrink immediately.
