Spaced repetition: why you forget by Wednesday

You can score well on a Sunday night quiz and still blank on Wednesday. That is not a character flaw. Your brain dumps what it thinks you will not need again.

Cramming works for tomorrow morning. It is a bad plan for a course that lasts 12 weeks.

The cheap version of the science

Each time you recall something just before you would have forgotten it, the memory gets cheaper to keep. Wait too long and you are learning it again from scratch. Review too soon and you waste time on cards you already own.

That gap is the whole method. Not prettier notes. Not a longer highlight session. A reminder at the right moment.

A schedule you can run by hand

• Day 0: first pass, right after class.
• Day 1: quick pass. Kill the cards you still miss.
• Day 3: another pass. Only the shaky ones if you are short on time.
• Day 7, then day 16. Stretch the gap when a card feels easy.

If a card is easy two times in a row, push it further out. If you miss it, bring it back to tomorrow. That is the whole algorithm, minus the math.

Three piles on your desk

No app needed for a small deck. Green: you said it out loud without peeking. Yellow: you got there after a hint. Red: wrong or blank.

Tomorrow, start with red. Then yellow. Green can wait. People fail spaced repetition because they shuffle the whole deck every night and get bored.

Let the app hold the calendar

Once you have more than one subject, a paper calendar gets messy. Quiz Genius tracks which cards you know and brings the weak ones back first. You still have to sit down. You do not have to remember that anatomy set from Thursday.

Pair it with short sessions. Ten minutes on the train beats a two-hour Sunday binge that you dread all week.

What not to do

• Do not add 200 new cards the night before a test and call it spaced repetition.
• Do not mark a card as known because the wording looks familiar. Say the answer first.
• Do not skip a day and then "catch up" with a 90-minute grind. Do the overdue pile. Stop.

If your current plan is reread-and-hope, switch one subject to cards this week. Download Quiz Genius, make a set from one lecture, and do the day-1 review tomorrow. That is enough to see if the method fits you.