Lesson objective: Understand that the meaning of addition does not change when different strategies are used.

Students bring prior knowledge of understanding addition as putting together and adding to from K.OA.A.1. This prior knowledge is extended to understanding that using different strategies does not change the meaning of addition as students use put together and count on strategies to show the same totals. A conceptual challenge students may encounter is understanding that two different strategies can be used to solve addition.

The concept is developed through work with two different colored snap cubes, which help students model their thinking and develop understanding of number partners and counting on as strategies to solve addition.

This work helps students deepen their understanding of equivalence because they will see that two different strategies can produce equivalent totals.

Students engage in Mathematical Practice 1 (Make sense of problems and persevere in solving them) as they use snap cubes to model two count on and number partner strategies.

**Key vocabulary:**

- count on
- number partners
- total

**Special materials needed:**