Half an hour. That's the whole trick.

People ask me how much homework a primary-age child should be doing, usually with a slightly guilty look, as if there's a correct answer they've been failing to provide. There isn't, really. But if you pushed me, I'd say half an hour, most school nights, and I'd stop there.

That's it. That's the trick. Short and regular beats long and occasional, every single time.

Why short wins

A seven-year-old has a limited tank of concentration, and it empties faster than we'd like. The first fifteen minutes of homework are worth a lot. The next fifteen are worth a bit less. By minute forty-five you're not teaching anything, you're just both getting cross, and the lasting memory your child files away is "maths is the thing that ruins the evening".

You don't want that memory. The maths matters far less than how they feel about doing the maths. A child who thinks homework is a normal, finite, slightly boring part of the evening will keep doing it for years. A child who thinks it's a punishment will fight you at every step.

So when the half hour is up, stop, even mid-sheet. Finishing isn't the goal. Turning up is the goal.

Why regular wins

Here's the maths on the maths. Twenty minutes a night, five nights a week, is over an hour and a half. A two-hour blitz on a Sunday, dreaded all weekend and resented by both of you, is less time and far less learning, because cramming doesn't stick and a tired child at the end of the weekend takes nothing in.

Little and often also keeps things ticking over so nothing goes properly cold. A topic touched every week never has to be relearned from scratch. A topic left for a month does.

What half an hour actually looks like

In our house it's usually a few maths questions, a short spell of reading, and a handful of spellings or a couple of times tables. Nothing heroic. Some nights it's lighter. Some nights, frankly, it doesn't happen at all, because life happens, and that's fine too. The aim is a habit, and habits survive the odd missed day.

The other thing I'd say is do less, but look at it properly. Six questions you actually mark and talk through are worth more than twenty your child raced through while you weren't watching. When you mark it yourself, you spot the one wobble that's worth five minutes of your attention. That's the whole return on the half hour.

If homework is currently a nightly war in your house, try shrinking it before you try anything else. Set a timer for thirty minutes, do what you can in that time, and stop when it goes off, cheerfully, no matter where you've got to. You might be surprised how much more gets done when everyone knows there's a finish line.