The work of this lesson connects to previous work because students have solved problems involving multiplication of teen numbers in ways that make sense to them. In the previous section they also used the distributive property to find products of single-digit factors using facts they know. In this lesson, students consider and connect different representations of a strategy used in the previous section that can also be used to multiply a teen number. This will be helpful in the next lesson when students solve these types of problems and choose how to represent the problem.
Activity 1: A Factor Greater than Ten
- Make sense of representations of multiplication (base-ten blocks and area diagrams) where one factor is a teen number.
- Let’s make sense of some ways to represent the multiplication of teen numbers.
Materials to Gather
|Activity 1||20 min|
|Activity 2||15 min|
|Lesson Synthesis||10 min|
Teacher Reflection Questions
- Compare (1–5), Stage 2: Add and Subtract within 20 (Supporting)
- How Close? (1–5), Stage 4: Add to 1,000 (Supporting)