📊Lesson 3.1 Outline- Multiplication is Repeated Addition (For Teacher- Do Not Publish)

Lesson 3.1

For full lesson outline please see  Advantage Math Lesson 3.1.

Standards:

4.NBT.5- Use strategies based on place value and the properties of operations to multiply a whole number of up to four digits by a one-digit whole number, and multiply two, two-digit numbers.

Objectives:

Math Objective: Students will be able to use repeated addition to multiply two-digit by one-digit whole numbers.

Language Objective: Students will be able to discuss with a partner how doubling numbers helps solve repeated addition problems.

Vertical Alignment:

3.OA.7.B- Know from memory all products of two one-digit numbers 

4.NBT.5- Use strategies based on place value and the properties of operations to multiply a whole number of up to four digits by a one-digit whole number, and multiply two, two-digit numbers.

5.NBT.5- Fluently multiply multi-digit whole numbers using the standard algorithm

Common Misconceptions:

None noted in Advantage Math for Lesson 3.1

Lesson Outline:

🚀Launch A (in class or remote)

  • Students will work with and show what multiplication from a one-digit by one-digit multiplication looks like. This concept is review from 3rd grade. 
    • Questions you could ask:
      • What do you remember about multiplication from 3rd grade?
    •  Vocabulary words: Commutative Property of Multiplication, Factor, Multiplication, Product

🤔Explore A (in class or remote)

  • Students are exploring the commutative property and how it can relate to repeated addition. 
    • Insert a video explaining the commutative property. This can be a simple visual using base ten blocks or even cuisinare rods that show 5 X 2. The problem that is presented should be simple and comfortable for the students so the focus is on what the commutative property is and not understanding the numerals component. 
    • Questions you could ask:
      • How does the commutative property change how a problem looks visually?
      • What do repeated addition and multiplication have in common?
      • Do you think that the commutative property could be a helpful tool as you progress in math and solve more challenging problems. 

💬Discuss A (in class or remote)

  • Questions to use in your discussion:

    • What is difference in the work involved in the two problems?

    • Is doing repeated addition a helpful skill when solving problems where both factors are large numbers? 

🚀Launch B (in class or remote)

    • Students are showing or describing what the word "double" means to them. 
  • Questions to ask:
    • When have you heard of the word double?
  • Vocabulary: repeated addition

🤔Explore B (in class or remote):

  • Have students watch "Interpret products using repeated addition". 
  • Students could solve the questions in a number of ways but the concept of repeated addition should allow some of the problems to be easier. 
  • Questions to use in your discussion:
    • Did you use repeated addition?
    • What multiplication problems do you see in each problem?

💬Discuss A (in class or remote)

  • Questions to use in your discussion:
    • What did you notice as you solved the problem while following the directions?

Additional Resources:

    • Ways to make remote:
      • Create an assignment and insert the video. Have students watch the video and answer questions that you create based on the needs of your students.
  • Read pages 237 and 238 in Elementary and Middle School Mathematics by Van de Walle, et al. (2013) to read about the strategies used by students.

 

  • Differentiation (in class or remote)
    • Challenge: Ask students to show a different strategy for adding the same number by not using doubles. For example, if multiplying 63 × 5, the 63 could be added by keeping a running total. Compare which strategy is more efficient.
      • Ways to make remote:
      • Students can do this challenge on their own and submit their work and thoughts. 
    • Struggling : With students, review repeated addition for one-digit by one-digit multiplication. Also review adding doubles.
      • Ways to make remote:
      • Have students join you in an online meeting format (Zoom or Teams) and do the exact same activity. They might not have the place value disks, but you can show them yours to discuss.

 

  • Lesson Extension (in class):
    • As an extension, have students create one-digit by two-digit multiplication problems using dice. Roll the dice and create a multiplication problem with the digits that appear on the dice. Any order is fine. Then have them solve the equations and draw a star next to the problems where they used doubles in repeated addition to solve.