← Back to the activity

Grade 2 Math — Adding within 100

Add two two-digit numbers.

Name: ________________________

Before you start

Walk along the line and watch the tens go past. Every number with a label under it is ten more than the one before.

0102030405060708090100

Adding 46 + 18 is two walks along this line: ten more carries you from 46 to 56, and eight more steps lands you on 64. That is the same as putting the tens together and then the ones.

  1. 1.Sort these sums by whether the ones must make a new ten.

    Groups: No new ten · Makes a new ten

    • 61 + 29
    • 46 + 18
    • 27 + 35
    • 35 + 22
    • 50 + 43
    • 23 + 14

  2. 2.Match each sum to its answer.

    • 23 + 40
    • 18 + 25
    • 52 + 36
    • 49 + 22
    • 88
    • 43
    • 71
    • 63

  3. 3.61 + 29 = ?

  4. 4.38 + 47 = ?

  5. 5.Which sum gives the biggest answer?

    • a) 27 + 26
    • b) 24 + 31
    • c) 43 + 12
    • d) 18 + 39

  6. 6.19 + 26 = ?

  7. 7.Put these sums in order, smallest answer first.

    • 35 + 22
    • 23 + 14
    • 46 + 18
    • 38 + 47

  8. 8.Tap the number that is one ten more than 47.

    Mark the line with an X.

    4042444648505254565860

Answer key — Grade 2 Math — Adding within 100

  1. 1. 23 + 14 → No new ten; 46 + 18 → Makes a new ten; 35 + 22 → No new ten; 27 + 35 → Makes a new ten; 61 + 29 → Makes a new ten; 50 + 43 → No new ten
  2. 2. 23 + 40 → 63; 18 + 25 → 43; 52 + 36 → 88; 49 + 22 → 71
  3. 3. 90
  4. 4. 85
  5. 5. d) 18 + 39
  6. 6. 45
  7. 7. 1. 23 + 14 2. 35 + 22 3. 46 + 18 4. 38 + 47
  8. 8. 57