Every silly mistake has a name

There is a sentence almost every 11+ parent says, usually on a Sunday evening, usually holding a marked paper.

“He knew it. He just made a silly mistake.”

The mock comes back at 71. Eleven marks gone. And when you sit down together and go through the paper, the strange part is how little of it is mysterious. He reads the question again, groans, and fixes it in ten seconds. He did know it. Nine of the eleven lost marks were things he can do.

Which is comforting, in a way, and completely maddening in another. Because if he knows it, what exactly are you supposed to practise?

Why “careless” isn’t a diagnosis

“Careless” is the word we reach for because the mistakes look random. One question he misread, one where he forgot to carry, one where he answered a slightly different question than the one on the page. No theme, apparently. Just a child being ten.

But here is the thing you notice if you keep the marked papers and lay three of them side by side: the mistakes are not random. Random mistakes would scatter — a different slip every week, no shape to any of it. Real mistakes cluster. The same wrong turn shows up in week one, week three and week five, wearing a different costume each time. Sweets in one paper, pocket money in the next, a length of ribbon in the third — and underneath, the identical move.

Random mistakes scatter. Real mistakes repeat.

“Careless” hides this. It files ninety different errors under one label, so every week feels like starting again. The child gets told to “slow down” and “read the question properly”, which is advice on the same level as telling someone with a limp to walk better. It names the symptom, not the cause.

What a named trap is

A trap is a specific, repeatable wrong turn — described precisely enough that you can recognise it the moment it happens again.

Take one of the most expensive in the whole 11+ syllabus. A question says: Amara has 24 stickers. She gives away a quarter, then puts a third of the rest in her album. Ask a room of ten-year-olds how many go in the album and a reliable share of them will answer eight — a third of 24. The 18 stickers that were actually left never entered the working. The child grabbed the only number in sight and took the fraction of that.

That move has a name in our library: of the rest. Not “careless with fractions”. A precise wrong turn: taking the fraction of the original amount instead of what was left. Once you know its name, you will see it everywhere — because it isn’t really a fractions mistake at all. It resurfaces in percentages a year later, in a question about a sale price, and the child who fell for it with stickers falls for it again with discounts.

Or take a second one, which we call the place shift. Multiplying by 10 or 100 shifts every digit; children are taught to “move the decimal point”, and under time pressure the point moves the wrong way, or the wrong number of places, and 3.7 × 100 comes out as 37. It quietly costs marks in decimals, in measures, in money questions — anywhere the units quietly change inside a word problem.

A named trap has three properties that “careless” doesn’t:

• It is specific enough to recognise on sight, in any costume.
• It is repeatable — the same child falls for the same trap in a predictable way.
• It is practisable — you can build ten questions that spring exactly this trap and nothing else.

Naming changes what you practise

Here is the practical difference, and it is the whole point.

Without a name, the response to a lost fractions mark is “more fractions”. Another full topic, most of which the child can already do, with the actual wrong turn buried somewhere inside it — or not present at all. Practice becomes a volume exercise, and the score drifts rather than moves.

With a name, the response is ten minutes on the exact move. Three or four questions where “of the rest” appears, each in a different costume, done slowly at the kitchen table with one question in the air: a third of what, exactly? That is a session a tired child can face on a Tuesday, and it targets the actual leak.

Naming changes the marking too. Instead of counting how many were wrong, you start noting which ones — and sorting them. Three wrong answers that share a name is not three accidents. It is one finding, and findings are things you can act on.

Start with the piles

You do not need anything special to begin. Next time a paper comes back, resist the urge to total it up first. Take the wrong answers and sort them into piles that feel alike — not by topic, but by the move that slipped. Grabbed the wrong number. Flipped the subtraction. Stopped one step early. Give each pile a name, even a silly one. Your names will be rougher than ours, but they will be yours, and they will repeat — which is exactly what makes them useful next month, when you can check whether a pile has shrunk.

The pattern is what you are after. The score is just the shadow it casts.

If you would rather not build the vocabulary yourself, that is essentially what we spend our time doing — you can see how the whole routine works on how it works.