Why does my child think they know their tables when they don't?

A child who confidently says 'I know my sevens' and then fails on a random question hasn't been dishonest — they genuinely believe they know. The research explains exactly why this happens, and why distributed practice prevents it.

What the research says

A randomized study — published in Applied Cognitive Psychology — tested what happens when students either cram their math practice into one session or spread it across three sessions over three weeks, then sit a test one month later.

The results had two parts. First, the expected finding: spaced practice produced significantly higher test scores. Second, a finding that gets less attention: students who crammed were grossly overconfident about their performance. Immediately after their concentrated practice session, they predicted scores far above what they actually achieved. Students who practiced in spaced sessions, by contrast, predicted their scores accurately — because they had experienced the forgetting between sessions and knew exactly where their gaps were.

This overconfidence matters practically. If a child (or parent) believes a table is “done,” they stop practicing it. The feeling of fluency during a massed session is real — but it doesn’t last. What’s being experienced is familiarity, not memory.

What this means in practice

The most reliable test of whether a fact is learned is not how confident your child feels, but how accurately and quickly they can retrieve it days later, in a random question, without any warm-up. Concentrated drilling produces temporary fluency that feels like permanent mastery — and that illusion is the most common reason practice stops too early.

Try this

• After a practice session, wait two days and then test the same facts without warning. The gap between session performance and delayed test is the real measure of retention.
• If your child’s confidence and their actual recall don’t match, that’s a sign practice has been concentrated rather than distributed.
• Don’t let a confident session be the signal to move on. Let a confident delayed test be that signal.

Last reviewed: 2026-08-01