### Lesson plan

# Repeated Addition and Multiplication

#### Learning Objectives

- Students will be able to use repeated addition as a strategy to multiply two single-digit factors.

#### Introduction

*(3 minutes)*

- Draw two circles on the board with five dots in each. Ask students what
**addition**problem you’ve drawn (**5 + 5**). Write the addition problem on the board. - Review the term repeated addition and explain: Each of these circles have five dots, so we are adding the same number twice. This is called
**repeated addition**because we are adding the same number, or equal groups,**repeatedly**. - Connect to multiplication and explain, "
**Multiplication**is another way to add equal groups. So, when we see an addition problem with equal groups, like this one, we can also think of it as a multiplication problem. We have two equal groups of five, so two times five is equal to**5 + 5**." - Tell students, "Today we are going to practice using repeated addition as a strategy to multiply."

#### Explicit Instruction/Teacher modeling

*(7 minutes)*

- On the board, draw four cookies with three chocolate chips in each (4 groups of 3).
- Give context by telling students that someone made cookies with three chocolate chips in each.
- Explain, "In this problem, we need to add the number 3 (write 3 under each cookie on the board) 4 times (emphasize by counting aloud how many cookies there are) to find the total number of chocolate chips. So, we have 4 groups of 3."
- Write a repeated addition expression (
**3 + 3 + 3 + 3**). - Ask a student to solve (12 chocolate chips).
- Remind students that when we are adding the same number repeatedly, then we can use multiplication. Write a multiplication equation (
**4 x 3 = 12**) and say, "4 groups of 3 is 12." - Draw another model (
**5 x 4**) on the board. - Ask students to talk with a partner and come up with an addition expression. Call on a student and write the expression as repeated addition on the board (
**4 + 4 + 4 + 4 + 4**). - Ask students to talk with a partner and come up with a multiplication expression. Call on a student and write the expression as multiplication on the board (
**5 x 4**). Read the problem as "5 groups of 4." - Call on a student for a solution and write the answer on the board.

#### Guided Practice

*(25 minutes)*

- Play the On a Roll with Multiplication game.
- Model this game for students by rolling two dice. Create a model using the numbers on the dice. Lay out paper plates for the number of groups and place linker cubes on each plate. For example, if you rolled 2 and 6, you would lay out two plates and place six linker cubes on each plate.
- Then, on a sheet of paper write a repeated addition equation and a multiplication equation to go with the model you built (i.e.
**6 + 6 = 12**and**2 x 6 = 12**) - Hand out six paper plates, two dice, 36 linker cubes, and a sheet of paper to each pair of students.
- Write the rules of the game on the board for student reference:
- 1) One partner rolls a die to decide how many groups there will be, 2) the other partner rolls to decide how many will be in each group, 3) as a team build a model, 4) write an addition and multiplication problem to go with the model.

- Instruct students to build four or more problems with their partner. (Note: Have students number their problems on their paper as they record so that you can see how many models they have built.)

#### Independent working time

*(15 minutes)*

- Hand out the Repeated Addition worksheet.
- Instruct students to complete the worksheet independently.
- Circulate and offer support as needed.
- Review the worksheet as a class.

#### Differentiation

**Enrichment:**

- During the dice game (On a Roll with Multiplication), have students roll two dice to determine how many linker cubes to place inside each group. This will increase the size of factors up to 12. (Note: in this scenario, students will need 72 linker cubes or other manipulative, like dry beans or macaroni).

**Support:**

- Provide pre-drawn models and ask students to write a repeated addition problem to go with the model.
- Provide a repeated addition problem and ask students to write it as a multiplication problem.

#### Assessment

*(5 minutes)*

- Hand out a sticky note to each student.
- Draw a model on the board and have students write a repeated addition problem and a multiplication problem with a solution on their sticky note.
- Collect student responses as an exit card and check for understanding.

#### Review and closing

*(5 minutes)*

- Play the repeated addition song to your students.
- Ask students to come up with repeated addition and multiplication problems to go with the song (i.e.
**2 eggs + 2 eggs = 4 eggs**;**3 flapjacks + 3 flapjacks = 6 flapjacks**).