Lesson Plan: Missing Numbers in Addition and Subtraction Equations Mathematics • 2nd Grade
This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to find any unknown in an addition or subtraction equation within 20 and find multiple ways of completing two missing unknowns.
Objectives
Students will be able to
- represent equations with missing numbers using part–whole models,
- count on or back to find a missing number in addition or subtraction equations,
- use inverse operations to find a missing number in addition or subtraction equations,
- find two unknowns in an addition equation (find multiple solutions or try to find all solutions),
- find two unknowns in a subtraction equation (find multiple solutions or try to find all solutions).
Prerequisites
Students should already be familiar with
- reading, writing, and solving addition and subtraction equations,
- adding and subtracting within 20.
Exclusions
Students will not cover
- calculating using numbers greater than 20.