Year 1: Adding equal groups

Key words. Equal groups have the same number of stars in each group.

Method. Add the same number 2 times, once for each group. Each group has 4.

1. Write one 4 for each group. There are 2 groups, so there are 2 numbers to add.
   4 + 4
2. Add the numbers together. Count in 4s to add them up: 4, 8.
   4 + 4 = 8
3. Write the answer.
   8

Check. Count in 4s: 4, 8. The last number is 8. ✓

Watch out. Write one number for every group. Do not write the number of groups instead.

Key words. Equal groups have the same number of cubes in each group.

Method. Add the same number 3 times, once for each group. Each group has 2.

1. Write one 2 for each group. There are 3 groups, so there are 3 numbers to add.
   2 + 2 + 2
2. Add the numbers together. Count in 2s to add them up: 2, 4, 6.
   2 + 2 + 2 = 6
3. Write the answer.
   6

Check. Count in 2s: 2, 4, 6. The last number is 6. ✓

Watch out. Write one number for every group. Do not write the number of groups instead.

Key words. Equal groups have the same number of balls in each group.

Method. Add the same number 4 times, once for each group. Each group has 5.

1. Write one 5 for each group. There are 4 groups, so there are 4 numbers to add.
   5 + 5 + 5 + 5
2. Add the numbers together. Count in 5s to add them up: 5, 10, 15, 20.
   5 + 5 + 5 + 5 = 20
3. Write the answer.
   20

Check. Count in 5s: 5, 10, 15, 20. The last number is 20. ✓

Watch out. Write one number for every group. Do not write the number of groups instead.

Key words. Equal groups have the same number of marbles in each group.

Method. Add the same number 3 times, once for each group. Each group has 5.

1. Write one 5 for each group. There are 3 groups, so there are 3 numbers to add.
   5 + 5 + 5
2. Add the numbers together. Count in 5s to add them up: 5, 10, 15.
   5 + 5 + 5 = 15
3. Write the answer.
   15

Check. Count in 5s: 5, 10, 15. The last number is 15. ✓

Watch out. Write one number for every group. Do not write the number of groups instead.

Key words. Equal groups have the same number of pears in each group.

Method. Add the same number 4 times, once for each group. Each group has 2.

1. Write one 2 for each group. There are 4 groups, so there are 4 numbers to add.
   2 + 2 + 2 + 2
2. Add the numbers together. Count in 2s to add them up: 2, 4, 6, 8.
   2 + 2 + 2 + 2 = 8
3. Write the answer.
   8

Check. Count in 2s: 2, 4, 6, 8. The last number is 8. ✓

Watch out. Write one number for every group. Do not write the number of groups instead.

Method. Find the number that fits in each box, so that three equal numbers make 9.

1. Try 3 in each box. Three threes make 9, so each box has 3.
   3 + 3 + 3
2. Add the three numbers. Count in 3s to check: 3, 6, 9.
   3 + 3 + 3 = 9
3. Write the answer.
   3 goes in each box.

Check. Each box has 3, and 3 + 3 + 3 = 9. ✓

Watch out. Count in the number you put in each box. You should land on 9.

Key words. Equal groups have the same number of sweets in each group.

Method. Add the same number 4 times, once for each group. Each group has 3.

1. Write one 3 for each group. There are 4 groups, so there are 4 numbers to add.
   3 + 3 + 3 + 3
2. Add the numbers together. Count in 3s to add them up: 3, 6, 9, 12.
   3 + 3 + 3 + 3 = 12
3. Write the answer.
   12

Check. Count in 3s: 3, 6, 9, 12. The last number is 12. ✓

Watch out. Write one number for every group. Do not write the number of groups instead.

Key words. Equal groups have the same number of flowers in each group.

Method. Add the same number 5 times, once for each group. Each group has 2.

1. Write one 2 for each group. There are 5 groups, so there are 5 numbers to add.
   2 + 2 + 2 + 2 + 2
2. Add the numbers together. Count in 2s to add them up: 2, 4, 6, 8, 10.
   2 + 2 + 2 + 2 + 2 = 10
3. Write the answer.
   10

Check. Count in 2s: 2, 4, 6, 8, 10. The last number is 10. ✓

Watch out. Write one number for every group. Do not write the number of groups instead.

Method. Add up the numbers in each sum, then compare the totals.

1. Add the first sum. Five plus five plus five.
   5 + 5 + 5 = 15
2. Add the second sum. Three plus three plus three plus three plus three.
   3 + 3 + 3 + 3 + 3 = 15
3. Compare the totals. If both totals are the same, Mia is right.
   15 = 15
4. Write the answer.
   Yes. Both sums make 15.

Check. Count in 5s to 15: 5, 10, 15. Count in 3s to 15: 3, 6, 9, 12, 15. ✓

Watch out. Different sums can make the same total. Add each sum to check.

Method. Find the total for each person. Then compare.

1. Add Ali’s sweets. Two bags with 3 in each bag.
   3 + 3 = 6
2. Add Jo’s sweets. Three bags with 2 in each bag.
   2 + 2 + 2 = 6
3. Compare the totals. Both totals are 6, so the numbers are the same.
   6 = 6
4. Write the answer.
   Neither. They both have 6 sweets.

Check. Count in 3s to 6: 3, 6. Count in 2s to 6: 2, 4, 6. ✓

Watch out. Different groups can have the same total. Count the sweets, not the bags.