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Year 2 Maths — Making and breaking tens

Swap ten ones for one ten, and break one ten back into ten ones.

Name: ________________________

Before you start

Thirty ones in a row, with a number written at every fifth mark. Move along the line and see where the tens fall.

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Counting on ten ones lands you exactly on the next ten. That is what swapping ten ones for one ten does — the same place on the line, reached a shorter way.

  1. 1.Work out each sum, then put them in order, smallest answer first.

    • 19 + 5
    • 49 + 9
    • 28 + 6
    • 37 + 8

  2. 2.Sort these sums by whether you must break a ten open.

    Groups: No breaking · Break a ten

    • 76 − 41
    • 84 − 29
    • 45 − 15
    • 63 − 38
    • 52 − 27
    • 58 − 23

  3. 3.Sort these sums by whether you must make a new ten.

    Groups: No new ten · Make a new ten

    • 36 + 29
    • 52 + 24
    • 41 + 32
    • 27 + 18
    • 23 + 15
    • 48 + 17

  4. 4.How many ones make one ten?

  5. 5.46 + 7 = ?

  6. 6.62 is 5 tens and how many ones?

  7. 7.31 − 4 = ?

  8. 8.13 ones is 1 ten and how many ones?

Answer key — Year 2 Maths — Making and breaking tens

  1. 1. 1. 19 + 5 2. 28 + 6 3. 37 + 8 4. 49 + 9
  2. 2. 58 − 23 → No breaking; 52 − 27 → Break a ten; 76 − 41 → No breaking; 63 − 38 → Break a ten; 45 − 15 → No breaking; 84 − 29 → Break a ten
  3. 3. 23 + 15 → No new ten; 27 + 18 → Make a new ten; 41 + 32 → No new ten; 36 + 29 → Make a new ten; 52 + 24 → No new ten; 48 + 17 → Make a new ten
  4. 4. 10
  5. 5. 53
  6. 6. 12
  7. 7. 27
  8. 8. 3