Most children sail through one to ten. They have been singing it since kindergarten. The real trouble starts at eleven, where English simply stops being systematic. Eleven and twelve look like nothing else in the language. Thirteen through nineteen at least share the teen ending, but thir and fif have already drifted away from three and five. A child who muddles this stretch isn't slow. The language really is playing tricks.
A Teaching Order That Cuts the Confusion
- Step 1: get one to ten completely solid, reading and writing, before you go anywhere near the rest.
- Step 2: teach twenty, thirty, forty and on to ninety before you touch eleven to nineteen. The tens are properly systematic, since twenty and thirty and the rest all end in ty, so children can grab the pattern.
- Step 3: build the two-digit numbers, twenty-one, thirty-five. Children feel as if they can suddenly count to a hundred, when in fact they have learned only a handful of new words.
- Step 4: come back for eleven to nineteen last and treat them as words to memorise. Tell the class plainly that this group breaks the rules and has to be learned by heart.
The Game for This Topic: Counting Circle Knockout
Sit the class in a circle and have them count one number each. Whoever lands on a number you have nominated, say anything ending in zero, claps instead of speaking. Miss it and you're out of the circle. The game forces children to listen to each other and think a few numbers ahead, and that's far deeper work than reciting a list in order.
The paper version of the same idea is a worksheet where children fill in the missing numbers in a sequence. It shows you straight away whether a child understands the system or has only memorised the running order.