Memory & Retention

Why does my child mix up 6×8 and 7×8?

Some times tables are hard not because they're hard to understand, but because they sit close to others in memory. Research shows this confusion is normal and lasting, which changes how you should handle it.

What the research says

Times tables aren’t stored as a list of separate facts but as a connected network. When your child tries to recall 7×8, nearby facts like 6×8 or 7×7 light up too, and their answers compete with the right one. That’s why so many mistakes are the correct answer to a neighbouring fact: 48 instead of 56 for 7×8.

Dotan and Zviran-Ginat (2022) showed that this matters most while facts are new. Year 2 pupils who learned different facts in the same week remembered them better than when that week’s facts were similar, and the difference could still be measured seven weeks after training ended.

A 2026 study by Eaves, Gilmore and Cragg followed adults as they learned multiplication facts they had never seen before (from 16×16 to 19×19). Interference between neighbouring facts appeared as soon as the facts started to be learned, and it didn’t shrink with practice, even once the facts were well known. The authors conclude that interference is a normal part of learning rather than a problem to prevent, and that it’s better managed, for example by encouraging children to pause and think, than avoided. The study was done with adults, so it shows the mechanism rather than exactly what happens in a classroom.

The same research group points out that some children are much more affected than others, because they find it harder to block out competing answers. When a child keeps mixing up certain pairs, it says more about that ability than about their maths knowledge (Guy, Cragg & Gilmore, 2025).

What this means in practice

Mix-ups between neighbouring facts are predictable, and they won’t disappear completely even once your child knows the tables. The aim isn’t to make them vanish but to give your child ways to catch them: slow down for a moment on the tricky facts, and know a quick way to check.

Try this

Find the pairs your child confuses: they’re usually the same ones, and usually neighbours (same table, next row) or facts with close answers. The blank times tables grid helps you find them.
When you introduce new facts, don’t introduce neighbours like 6×8 and 7×8 in the same week.
On the tricky pairs, ask for accuracy first, not speed. A short pause to think is fine.
Give your child a way to check: “7×8 is one more 8 than 6×8, so 48 + 8 = 56.” Knowing how facts are linked is a backup when memory wavers.
Keep bringing the tricky pairs back over the following weeks: they need more practice than the rest, not just one extra round today.

→ TabTabTab keeps track of the facts your child mixes up and brings them back more often, so the tricky pairs get the practice they need.

Sources

Dotan & Zviran-Ginat (2022) — peer-reviewed study
Eaves, Gilmore & Cragg (2026) — peer-reviewed study
Guy, Cragg & Gilmore (2025) — expert commentary

Last reviewed: 2026-10-17