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Addition within 20 for Class 1

What adding to 20 means, one worked example step by step, and 5 questions to try. No timer, no account.

What it means

Adding within 20 means joining two groups and counting the total, where the total is 20 or less. Children first count on, then learn a faster way: make ten, then add what is left.

Worked example: 8 + 5

  1. 1Start with 8. We need 2 more to fill a ten-frame.
  2. 2Split 5 into 2 and 3.
  3. 3Make ten: 8 + 2 = 10.
  4. 4Add what is left: 10 + 3.

8 counters2 moved from the 5 (3 still left)

So 8 + 5 = 13.

Practice 5 questions

Question 1 of 5

Printable worksheets

Prefer paper? These sheets print on A4 and each has an answer key on the last page.

Join and add on - Class 1 addition
Free printable PDF, with an answer key for grown-ups.PDF Make ten - Class 1 addition
Free printable PDF, with an answer key for grown-ups.PDF

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More topics

Subtraction within 20 Tens and ones More, fewer, equal All Class 1 topics

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