Lesson Plan

What's That Number?

Practice finding unknown numbers in addition equations using fun and silly word problems.
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Need extra help for EL students? Try the What's the Value? pre-lesson.
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Need extra help for EL students? Try the What's the Value? pre-lesson.

Learning Objectives

Students will be able to find an unknown number in an addition word problem.

The adjustment to the whole group lesson is a modification to differentiate for children who are English learners.
EL adjustments


(5 minutes)
What's Missing? Word Problems
  • Write a story problem up on the board. Read it aloud to your students. For example: "There are 20 animals in the tree. There 10 are snakes, and the rest are monkeys. How many monkeys are in the tree?"
  • Write out a corresponding equation to go with the word problem. For the problem above, write out: 10 + ________ = 20.
  • Ask them to turn and talk with a partner to share how they could solve this problem.


  • Provide students with visuals that connect to the word problem.
  • Pair students with a partner who speaks the same home language (L1), if possible.


  • Encourage students to rephrase the story problem in their own words to a partner to check for understanding.
  • Provide students with sentence stems, such as:
    • I can solve the problem by ________.
    • A strategy I can use is ________.

Related Guided Lesson

Place Value 3

9 games
1 song video
5 printable worksheets
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second grade
Subject Math