There's no magic number of hours. What matters far more than the total time is how that time gets spent.
25 August 2026 · 4 min read
It's a fair question, and one that doesn't have a single tidy answer — but there is a useful rule of thumb: short, regular sessions consistently outperform occasional long ones, at almost any age.
For most primary-age children, somewhere around 15–20 minutes, three to four times a week, is a reasonable target for focused, deliberate practice — separate from homework set by school. For older children working towards the 11+ or GCSEs, that might stretch to 20–30 minutes most days as exams approach. These aren't strict rules; a child who's engaged and making progress in less time doesn't need to be topped up to hit a number, and a child who needs longer on a particular week because of a specific gap shouldn't be cut off at an arbitrary limit either.
Three 15-minute sessions across a week generally do more for retention than one 45-minute session, even though the total time is identical. Spacing practice out gives the brain more separate opportunities to retrieve a skill from memory, which is what actually strengthens it — a single long session mostly just extends the first attempt. We covered why this spacing effect matters for retention specifically in why children forget maths they learned last year.
Neither frequency nor duration is worth much if the practice itself isn't doing anything useful. Twenty minutes spent on questions a child could already do without thinking builds very little; twenty minutes spent on the specific skill they're actually shaky on, at the right level of challenge, does considerably more — even though the clock reads the same. This is really the same point made in why more maths practice isn't always the answer: the amount of time is the least important variable in the equation.
Rather than chasing a specific number, it's more useful to watch for a few signals. Practice sessions that end with the child still reasonably engaged, rather than exhausted or checked out, are usually about the right length. Sessions that reliably surface one or two things worth working on — not zero, not an overwhelming list — suggest the difficulty level is roughly correct. And steady, if gradual, improvement over a few weeks is a better indicator than any single week's performance.
It's worth saying plainly: doubling the time doesn't reliably double the progress, and pushing a tired, frustrated child through an extra twenty minutes for the sake of hitting a target usually costs more in motivation than it gains in skill. If a session has stopped being productive, ending it early and coming back fresh the next day is very often the better call.
Grasp Maths is built around short, focused sessions rather than long marathons — each one aimed at the skills that actually need attention, so the time a child does spend practising is doing real work rather than padding out a number of minutes.
Don't just practise more. Practise what matters next.
Try a free Grasp Maths practice session and see how a focused 15 minutes can target exactly what's needed.