Subtraction – Unknown Addends


With our Subtraction – Unknown Addends lesson plan, students learn to think about subtraction problems as missing addend problems, deepening their understanding of subtraction problems and how to solve them. As a part of this lesson, students practice solving problems with this method and creating their own problems for classmates to solve.


Our Subtraction – Unknown Addends lesson plan teaches students how to look at subtraction problems as unknown addend problems. For example, to solve 12 – ? = 7, you can think of it as 7 + ? = 12, with the “?” being the unknown addend. During this lesson, students are asked to work with a partner to complete an activity in which they use physical blocks to create subtraction problems, which their partner has to solve. Students are also asked to solve written practice problems in order to demonstrate their understanding of the lesson material.

At the end of the lesson, students will be able to understand subtraction as an unknown addend problem.

Common Core State Standards: CCSS.Math.Content.1.OA.B.4

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