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Find the missing number: 1st grade math

Unknown in any position (8 + ? = 11). A free 1st grade lesson plan, a question set with answers and a printable sheet with its key. Copy it and make it yours.

Lesson plan

Goal

  • Students can do this: unknown in any position (8 + ? = 11).

Teach (10 min)

  • Think: what do I add to 3 to make 8?
  • Take the part you know from the whole.
  • Work one example on the board while students say each step aloud, then do one together.

Practise (15 min)

  • Students work the printable sheet in pairs, then alone.
  • Or practise it as a game with no sign-up: https://peabody.kids/math/numsense.g1_unknown?lesson=1-numsense-unknown-1&at=1

Exit ticket (5 min)

  • Three questions on a slip:
  • 1. Find the missing number: 9 + ? = 10
  • 2. Find the missing number: 8 + ? = 9
  • 3. Find the missing number: 2 + ? = 7

Question set

10 questions that read in words, easiest first. Questions that need a picture are on the printable sheet below.

  1. Find the missing number: 9 + ? = 10
  2. Find the missing number: 8 + ? = 9
  3. Find the missing number: 2 + ? = 7
  4. Find the missing number: 4 + ? = 6
  5. Find the missing number: 2 + ? = 5
  6. Find the missing number: 8 + ? = 10
  7. Find the missing number: 9 + ? = 10
  8. Find the missing number: 6 + ? = 8
  9. Find the missing number: ? + 1 = 5
  10. Find the missing number: 4 + 4 = ?
Answers
  1. 1
  2. 1
  3. 5
  4. 2
  5. 3
  6. 2
  7. 1
  8. 2
  9. 4
  10. 8

Printable sheet

Name: ____________________   Date: ____________

Find the missing number (1st grade)

  1. Find the missing number: 1 + ? = 7
  2. Find the missing number: 8 + ? = 10
  3. Find the missing number: 4 + ? = 5
  4. Find the missing number: 2 + ? = 9
  5. Find the missing number: 6 + ? = 10
  6. Find the missing number: ? + 2 = 10
  7. Find the missing number: ? + 2 = 5
  8. Find the missing number: ? − 2 = 8
  9. Find the missing number: 9 + 1 = ?
  10. Find the missing number: 6 + 3 = ?
  11. Find the missing number: 15 + ? = 16
  12. Find the missing number: 13 + 4 = ?
Key
  1. 6
  2. 2
  3. 1
  4. 7
  5. 4
  6. 8
  7. 3
  8. 10
  9. 10
  10. 9
  11. 1
  12. 17

Written by Peabody from its own skill pages. Free, no ads, no sign-in. Children can practise this on Peabody. More from teachers: teacher-shared resources.