### EL Support Lesson

# Strategies for Multiplying by Multiples of 10

#### Objectives

##### Academic

Students will be able to multiply a one-digit number by a multiple of ten.

##### Language

Students will be able to explain two strategies for multiplying by a multiple of ten using sentence stems and peer supports.

#### Introduction

*(2 minutes)*

- Facilitate a Think-Pair-Share to get students thinking about the strategies they use to solve multiplication problems.
- Have students think to themselves before turning and talking to a partner. Then, share out as a class.
- Tell students that they will be focusing on two strategies today as they multiply one-digit numbers by multiples of 10.

#### Explicit Instruction/Teacher modeling

*(8 minutes)*

- Distribute a copy of the Glossary to each student and have them follow along with the words as you display the Vocabulary Cards on the document camera. Read each word aloud and have the class repeat it. Then, do the same for the definitions.
- Tell the class that there are many strategies they can use to solve multiplication problems, and cite the examples that students brought up during the Introduction. Write the words
*Sketch*And*Underlining*On the board and share that these are the two strategies they will focus on today. - Share an example problem with a real-life scenario, such as "There are 30 houses in my neighbourhood and I want to make a bag of cookies for each house for the holidays. I'd like to put five cookies into each bag. How many cookies will I need to make?"
- Write the expression
**5 x 30 = ?**On the board and model each of the strategies next to each other to demonstrate how you arrive at the same answer with both strategies. - Explain that the sketch strategy is drawing a visual. Draw straight lines to represent base-ten sticks, and include the correct number of groups (represented by the one-digit number in the problem) in the drawing. Draw five groups of three lines, or five groups of 30. Count them up by skip counting and share that you must bake 150 cookies.
- Share the underlining strategy by drawing a line under the one-digit number, and the number in the tens place of the two-digit number. Underline the numbers five and three. This shows the basic maths problem
**5 x 3 = ?**That is easier to solve than a problem with large numbers. Write**5 x 3 = 15**. Explain that 15 represents the number of 10s, so another zero must be added. Again, the answer shows that I will need to bake 150 cookies. - Ask students to turn and talk to a partner about the strategies that were just shared. Have them focus on what they noticed about each and how they are similar and different. Provide sentence stems to support them, such as "I noticed that
**____**." and "The strategies are similar/different because**____**."

#### Guided practise

*(10 minutes)*

- Distribute a copy of the What Went Wrong? Multiplying by Multiples of 10 worksheet to each student and display a copy on the document camera.
- Review the sketch strategy by going over the example, and then have students turn and talk to a partner to rephrase how to use the strategy. Then, do the same for the underlining strategy.
- Model completing the first problem on the worksheet. Read aloud the problem and circle any important information that is helpful. Think aloud about how you will find the answer using the given strategy, and identify the mistake in the strategy. Show students how to fix the error by showing the work in the right column. Make sure students copy the teacher markings on their own paper.
- Complete the sentence stems at the bottom of the problem to explain what the mistake was and how to fix it.
- Engage the class in looking at the second example with the strategy completed incorrectly. Discuss the mistake as a class, and then put students into partnerships to fix it. Circulate and offer support and feedback as needed. Go over the problem as a class and provide sentence stems to support conversation. For example, "The mistake is
**____**." and "To fix the mistake, I can**____**."

#### Group work time

*(12 minutes)*

- Scramble partnerships and inform students that they will work together to critique the wrong responses on the remainder of the worksheet. Remind them that being able to notice mistakes helps us become detail-oriented mathematicians who can analyze maths problems and solutions with a critical eye.
- Instruct students to identify the errors in the final three problems on the worksheet and discuss how they could fix the problem. Remind them to use key vocabulary, relying on the Glossary as a reference as needed. Encourage them to talk about each step of the process as they form the new response.
- Have partners share out the complete sentence stems with their error analysis and suggested solution for each problem. Engage the rest of the class in sharing if they agree or disagree with the responses that are shared. Provide a sentence stem to support discussion, such as "I agree/disagree because
**____**."

#### Additional EL adaptations

**Beginning**

- Allow access to reference materials in home language (L1).
- Have learners repeat instructions and key vocabulary to the teacher.
- Provide a word bank of key terms and phrases for students to use in group and class discussions.
- Group students intentionally based on academic and language needs.
- Give learners their own set of Vocabulary Cards to reference throughout the lesson.

**Advanced**

- Allow learners to utilize glossaries and dictionaries for unfamiliar words.
- Have students describe their maths processes without relying on the sentence stems/frames.
- Choose advanced ELs to share their ideas first in group and class discussions.
- Have learners repeat instructions and key vocabulary, summarizing important information for the class.

#### Assessment

*(5 minutes)*

- Give each student an index card and have them choose which strategy they'd like to focus on. Have them write
*Sketch*Or*Underlining*On the top of their card based on their choice. - Instruct students to write down the steps they must take to use that strategy to solve a multiplication problem with a multiple of 10.

#### Review and closing

*(3 minutes)*

- Create a chart based on students' Exit Tickets for each of the strategies they can use to solve a multiplication problem with a multiple of 10. Show the sketch strategy and the underlining strategy next to each other on the chart so students have an easy visual to compare the two options.
- Remind learners that a detailed mathematician is able to look at a strategy and identify errors, which allows them to self-check and make sure they arrive at the correct answer.