Back to Blog
Science & Method

The Science of Spaced Repetition in Language Learning

Dr. Alex Miller 2026-05-20 5 min read

Have you ever spent hours cramming English vocabulary words before an exam, only to forget almost all of them a week later? You are not alone. This is the natural result of the human brain's memory architecture, first mapped out by German psychologist Hermann Ebbinghaus in 1885 as the Forgetting Curve.

What is the Forgetting Curve?

The Forgetting Curve demonstrates that without active review, our memory of new information drops exponentially within the first 24 to 48 hours. In fact, humans forget about 50% of new information within an hour of learning it. By day seven, retention falls below 10%.

Enter Spaced Repetition (SRS)

Spaced Repetition is a learning method that schedules reviews of vocabulary at increasing intervals. Instead of reviewing a word every day, you review it just as you are about to forget it. Each successful recall reinforces the neural pathways, flattening the forgetting curve and moving the word from short-term to long-term memory.

Why ChunkMaster Uses SRS

By using the SuperMemo-2 (SM-2) algorithm, ChunkMaster monitors your recall scores (Again, Hard, Good, Easy) and dynamically spaces out your review sessions. This ensures you spend zero time reviewing words you already know, and focus only on the words that are slipping away. It is the most scientifically efficient way to acquire vocabulary.

Start Studying Smarter Today

Join thousands of language learners using our scientific spaced repetition scheduler. Access Oxford CEFR vocabulary and sync all your cards.

Sign Up for Free