They handle 1–10 without trouble. Then comes 11, 12, 13... and something happens. "Eleven, twelve, thirteen... thirteenteen? Fourteen? Fifteen?" The 10–20 stretch is the first hard bit in counting. And if it doesn't stick — then 20–100 doesn't either. This article shows why, and how to train 11–20 so it becomes as easy as 1–10.
At Kluriko 10–20 is seen as the first critical step in maths development. Learning Games train this number range, but at home — with fingers, sticks and dice — real learning happens.
Why is 11–20 hard?
1. Irregular language. In Swedish: "elva, tolv, tretton" — at 13 the system switches and we get numbers like "tretton" (three + ten). It's logical but not through 11–12. Many kids get confused here. (English: "eleven, twelve, thirteen" has the same problem.)
2. Ten is invisible. 13 = 10 + 3. But they just see "thirteen" as one word. They need to understand the number is made of ten plus three.
3. Pattern breaks. In 1–10 every number is one word. In 11–20 some are tricky ("twelve", not "two-ten"), some are logical ("fifteen" = five + ten).
4. The base-ten system is abstract. They start to grasp our number system is base ten. A big idea that takes time.
How to teach 11–20
Step 1: Hands-on counting with fingers and sticks
Lay 10 sticks in a row. "That's 10. Now I add one. How many?" They count: "10... 11!" Show 10 + 1 = 11. Then 10 + 2 = 12. Then 10 + 3 = 13.
This is concrete understanding. They see that "thirteen" is ten plus three.
Step 2: Ten-bundles
Bundle ten sticks with a rubber band. "This is a ten." Then lay loose sticks next to it. "One ten plus three = thirteen."
This is eye-opening for many 5–6-year-olds. The abstract ten becomes concrete.
Step 3: Number line
Write 1, 2, 3... 20 on a long card. They point and count. Then skip rows: 2, 4, 6, 8, 10. They see patterns.
Step 4: 20-grid
Like the 100-grid but smaller. Visualises the number range. They see that 20 = two rows of 10.
Games for 11–20
Dice + dice = 11–20
Use two ten-sided dice (D10), or one die + one die + 10. The result is always 11–20. They count.
Clock counting
Clock hours are 1–12. They count around the clock. Good for a 6-year-old.
Jump 20 times
"Jump 20 times." They count aloud while jumping. Body + number.
Count stairs to 20
If there are long stairs — count each step. Up to 20.
Count cards
Count a card deck from 1 to 20. Then back. Then again.
Count down
"20, 19, 18... 1, 0!" They practise backwards. Hard but useful.
Pair to 20
"How many more to reach 20?" 15 + ? = 20. They train complements.
When are they ready for 11–20?
Age 5: they often say 1–20 in order, but don't always understand it.
Age 6: they count to 20 concretely. Know 13 is after 12.
Age 7: they understand 10 + 3 = 13. Base-ten starts to land.
Before 5: not worth pushing. They master 1–10 first.
Common problems
They say "twenty-one, twenty-two... twenty-thirteen". They mix the 20-row with the 10-row. Explain: after twenty-nine comes thirty (3 tens).
They can chant but not count. Can say 1–20 but can't pick up 13 stones. It's a one-to-one problem. Solve with physical counting games.
They think "twenty" is after "eleven". Some kids learn 11, 12, twenty. They haven't grasped the order. Help: count concretely with sticks.
They lose focus. OK. Counting practice is intense for a 5-year-old. 5 minutes is enough.
The base-ten system — the big idea
At 6–7 they start to understand our number system is base 10. One of the most important ideas in all maths education. Everything later builds on it.
Concretely: "23" = 2 tens + 3 ones. "47" = 4 tens + 7 ones. This unlocks counting for life.
Prepare with the 11–20 work. And later with 50 and 100.
Counting backwards — super hard
If they can count backwards from 20 to 0, they're very far ahead. Most 6-year-olds can't quite. But it's worth practising — it prepares subtraction.
How Kluriko helps
Kluriko Learning Games have counting games that train 1–20 in different formats: show quantity, point a number, pair a numeral with an amount. A good complement to the physical counting at home.