Lesson objective: Understand that the partial product method is a vertical representation of the calculations illustrated in the area model for multiplication.

Students bring prior knowledge of using the area model to solve multi-digit multiplication problems from 4.NBT.B.5. This prior knowledge is extended to include the partial products method as students learn to solve multi-digit multiplication problems. A conceptual challenge students may encounter is understanding the distributive property of multiplication.

The concept is developed through work with the area model, which is compared to the partial products method to develop conceptual understanding.

This work helps students deepen their understanding of operations because they compare the partial product method to the area model and determine that the partial products method is a vertical representation of the calculations illustrated in the area model for multiplication.

Students engage in Mathematical Practice 1 as they** **make sense of problems and persevere in solving them by comparing and contrasting the area model and partial products method for multiplication.

**Key vocabulary:**

- area model
- partial products