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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.

051015202530

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.

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

  2. 2.7 ones and 6 ones make 13 ones. How many tens is that?

    • a) 3
    • b) 1
    • c) 0
    • d) 2

  3. 3.Match each number to another way of writing it.

    • 34
    • 56
    • 71
    • 28
    • 6 tens 11 ones
    • 4 tens 16 ones
    • 1 ten 18 ones
    • 2 tens 14 ones

  4. 4.13 ones is 1 ten and how many ones?

  5. 5.46 + 7 = ?

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

    Groups: No breaking · Break a ten

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

  7. 7.Tap the number that is one ten more than 30.

    Mark the line with an X.

    0102030405060

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

    Groups: No new ten · Make a new ten

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

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. b) 1
  3. 3. 34 → 2 tens 14 ones; 56 → 4 tens 16 ones; 71 → 6 tens 11 ones; 28 → 1 ten 18 ones
  4. 4. 3
  5. 5. 53
  6. 6. 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
  7. 7. 40
  8. 8. 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