🔢 Numbers & shapes · Ages 6–7 · about 5 weeks

Adding and Subtracting within 100

Goal: Add and subtract two-digit numbers using tens and ones, and solve word problems.

For parents: Start with sums that don't cross a ten (34 + 5, 48 − 3), then adding tens (34 + 20), then the harder ones (38 + 7). Always ask 'How did you work it out?'

Do together

  1. Bundle sums

    You need: Straw bundles from the tens and ones unit

    Show 23 and 14 with bundles. Put the tens together and the ones together. How many altogether?

  2. Word problem stories

    You need: Paper

    Make up problems about your family: 'Ammi bought 25 eggs. We used 6. How many are left?' Draw it, then write the number sentence.

  3. Make ten to add

    You need: Ten-frames drawn on paper, counters

    Show 8 + 5: move 2 to fill the ten, 3 left over — 13. This trick works for 38 + 5 as well.

Talk about it

  • Should we add or take away? How do you know?
  • What is 40 + 30? What about 45 + 30?
  • Can you check your answer another way?

Words to use

  • add
  • subtract
  • sum
  • difference
  • altogether
  • left
  • word problem

Play

  • Add & Take Away
    Adding & taking away
  • Make the Number
    Number bonds
  • Ten-Frame Fill
    Ten frames
  • Number Train
    Number order
Play these games free

Every game is free for every family until 20 November 2026.

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