The answer is a number small enough that most parents don't believe it. And many of the parents who don't believe it are currently running two-hour weekend maths marathons that achieve less — at considerably higher cost in tears, bribes and Sunday-afternoon goodwill.
Here it is, up front, because you searched for a number and deserve one: 10 to 20 focused minutes a day. Roughly 10 minutes for ages 6–8, and 15–20 minutes for ages 9–12. Done daily, that modest dose reliably outperforms the weekend blitz — not because short sessions are virtuous, but because of how memory physically works.
The rest of this article explains why the small number wins, what "focused" actually means, and the one honest caveat: what 15 minutes a day can do, and what it can't.
Why six short sessions beat one long one
The effect has a name — the spacing effect — and it is one of the oldest, most replicated findings in the science of learning. In a large 2006 meta-analysis covering hundreds of comparisons, Cepeda and colleagues found that distributed practice (the same material spread over multiple sessions) reliably beats massed practice (one long session) for long-term retention.
The plain-words version: the brain does its consolidation between sessions, not during them. Learning is laid down while your child is doing something else entirely — sleeping, playing, arguing about dinner. Six short sessions across a week create six of those consolidation cycles. One Sunday marathon creates exactly one, plus about ninety minutes of fatigue dressed up as studying.
There's a second mechanism hiding in the schedule, too. Each new day, your child has forgotten a little — and having to reach back and retrieve yesterday's material is precisely the effort that strengthens it. The marathon never gets to use this, because nothing has time to be forgotten between minute 40 and minute 41.
Answering beats re-reading
How the minutes are spent matters as much as how they're spread. In a well-known pair of 2006 experiments, Roediger and Karpicke showed that testing yourself on material beats re-studying it for long-term retention — even though re-studying feels more productive at the time.
For maths, the translation is simple: ten minutes answering questions does more than an hour watching worked examples or re-reading notes. A child who spends their daily minutes retrieving — What's 7 × 8? What's half of 46? — is doing the thing that builds fluency. A child re-reading the textbook is mostly rehearsing the feeling of familiarity, which is not the same thing and evaporates under test conditions.
This isn't a niche opinion. When Dunlosky and colleagues reviewed ten common learning techniques in a major 2013 monograph, the two rated most effective were exactly these: distributed practice and practice testing. They also noted, a little mournfully, that these are among the techniques students use least.
Ten daily minutes of answering questions is both of them at once. That's the entire trick.
What "focused" means (and the difficulty rule that isn't optional)
Focused doesn't mean grim. It means three things.
One sitting, no half-attention. Ten real minutes — not twenty with a cartoon on. Short enough that full attention is actually achievable, which is much of why short works.
Retrieval, not consumption. The child is producing answers, on paper, out loud or on a screen — not watching or copying.
The right difficulty. This is the non-negotiable. Practice works in a narrow band — succeeding on roughly 7 or 8 questions out of 10. Below that, the session is a daily rehearsal of failure, and that rehearsal has consequences of its own. Above it, nothing is being stretched. For a Grade 4 child (Class 4 in India, Year 5 in England), the right ten minutes might be Grade 4 material — or it might be Grade 2 subtraction facts, if that's where the shaky floorboard is. The clock matters far less than the level.
Parents sometimes worry that such a small dose can't be serious. Consider the arithmetic instead: 15 minutes a day is over 90 hours a year, delivered in the highest-value format learning science knows. The two-hour Sunday session totals half that — in the lowest.
Making it automatic: same time, same trigger
The families who sustain daily practice almost never rely on discipline. They attach the minutes to something that already happens every day: right after breakfast, straight after the school run, while dinner is cooking. In Seoul it's before hagwon pickup; in São Paulo it's after football; in Mumbai it's while the tiffin box gets washed. The anchor doesn't matter. Having one does.
One family we heard from retired their dreaded Sunday two-hour session and replaced it with "maths with breakfast" — twelve minutes, every morning, phone timer on the table. The first thing that improved wasn't the marks. It was that nobody argued about maths any more, because twelve minutes isn't worth arguing about. The marks came along about six weeks later, the way they tend to: quietly, after the habit stopped being negotiable.
Consistency isn't a virtue here. It's the mechanism.
That's worth sitting with, because parents often frame streaks as a character-building bonus. They're not the bonus; they're the delivery system. The spacing effect is the streak — miss four days a week and you've dismantled the very thing that makes small doses work. It's also why we built Practice Points around daily showing-up rather than around marathon sessions: the reward tracks the mechanism, not the theatre.
The honest caveat: maintenance is not repair
Fifteen minutes a day at the right level will consolidate what your child knows and steadily extend it. What it won't do — at least not aimed at this year's syllabus — is close a gap that's two grades deep. A child who is shaky on Grade 5 work because a Grade 3 skill never landed doesn't need more minutes; they need the same minutes aimed backwards, at the missing prerequisite. If practice has been consistent for months and nothing is moving, the dose isn't the problem, and the real culprit is usually a skill from two grades ago.
Two related flags worth knowing: if your child is accurate but slow, that's usually a fluency question, not an ability question — and it responds beautifully to exactly this kind of short daily retrieval. And if the daily minutes are being spent on page after page of identical sums, the format is quietly wasting them; mixed, varied questions are what make retrieval do its work.
The whole answer in four lines
Ten minutes daily at ages 6–8; fifteen to twenty at 9–12. Answering questions, not re-reading. Pitched where your child succeeds on about 7 or 8 out of 10. Attached to a daily anchor so it happens without a negotiation.
That's the routine. The one hard part — knowing which questions, at which level, adjusted daily as your child moves — is the part a parent shouldn't have to engineer at the kitchen table. It's what CREST Champs' free daily adaptive practice does automatically: a short session each day, pitched at the edge of what your child can do, drifting backwards to a prerequisite when one is missing and forwards the moment it isn't. The minutes are yours; the aiming is ours.