### EL Support Lesson

# Mental Math Bingo with Multiples of 10

#### Objectives

##### Academic

Students will be able to add and subtract multiples of 10.

##### Language

Students will be able to mentally add or subtract 10 to a mutiple of 10 within 100 using sentence frames and hands-on activities for support.

#### Introduction

*(2 minutes)*

- Gather the students together in a comfortable area. On the whiteboard, write the following numbers: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100.
- Ask students to think-pair-share with an elbow partner what they notice about the numbers. Provide sentence stems such as:
- I notice the numbers are different because
**____**. - I notice the numbers are the same because
**____**. - Something I notice is
**____**. - Something I wonder is
**____**.

- I notice the numbers are different because
- Explain to the students that today they will be learning how to add and subtract 10 from multiples of 10. Elaborate that the numbers on the whiteboard are
**multiples**of 10.

#### Explicit Instruction/Teacher modeling

*(10 minutes)*

- Review the Vocabulary Cards with students, explicitly defining the words using the student-friendly definitions. Refer to the visual representations to support student understanding.
- Clarify any confusion about the vocabulary words, especially the mathematical concepts of
**integer**and**multiple**. Provide real-world context and examples when necessary. Next, allow students a few minutes to explain the definitions in their own words to elbow partners. - Provide sentence stems and frames to support students in sharing their ideas, for example:
- The word
**____**means**____**. - An example of
**____**is**____**.

- The word
- Allow a few partnerships to share their ideas with the class and jot down any key words, phrases, sentences, or visuals they use to refer back to throughout the lesson.
- Explain to the students that today they will be using mental math to add and subtract 10 from the numbers written on the whiteboard (e.g. 10, 20, 30, etc.).
- Ask students to think about a time when they used mental math. Allow a few students to provide examples and jot their ideas on the whiteboard.

#### Guided Practice

*(10 minutes)*

- Project the Always, Sometimes, Never worksheet on the whiteboard. Fill in "mental math" on the blank line on the top of the worksheet. Explain to the students that today, since they will be exploring mental math, you want them to think about some of the characteristics of mental math. Say, "The strategy we are going to try to use today is mental math.
**Mental math**means trying to solve math problems in your head without using manipulatives or other resources for support." - Write the following problems on the board:
**20 + 10 =****____****10 + 10 =****____****30 – 10 =****____**

- Explain to the students that you want them to try to solve the addition and subtraction problems using mental math. Have students jot down their answers on a scrap piece of paper. Allow a few students to share out their answers and clarify any misconceptions.
- Ask students to turn and talk with an elbow partner, sharing how they solved each problem using mental math or sharing what strategy they used instead. Provide sentence stems such as:
- I solved the problems in my head by
**____**. - I solved the problems by using
**____**(insert strategy).

- I solved the problems in my head by
- Ask a few of the students to share out how they solved the problems in their head. Answers may include: I just knew the answer, I counted up by 10, I imagined pictures in my mind, I imagined a number line, I left off the zeros and just added the numbers in the tens place, etc.
- Elaborate that mental math is a great strategy to use if we really understand a concept. Refer back to the Always, Sometimes, Never worksheet projected on the whiteboard.
- Take out the six notecards with pre-written words and phrases (ie. easy, hard, etc). Read each word/phrase aloud to the students. Have them help you determine if the word/phrase should be placed under always, sometimes, or never, when referring to the strategy of mental math.

#### Group work time

*(12 minutes)*

- Put students into groups of five and project the first page of the Mental Math Bingo activity on the whiteboard. Read the directions and clarify any questions students have about how to play. Pass out a different bingo board to four players in the small group along with a set of calling cards for one of the group members. Provide coins, rocks, or small circles to use as bingo chips.
- Refer to the top of the page and say, "Point to the multiples of 10 up to 100 on your worksheet. Let's count by 10's up to 100 aloud!" Lead students in a choral chant as they count by 10's up to 100.
- Have students count by 10's up to 100 with elbow partners.
- Explain to the students that the table on the top of their worksheet can be used as a resource for students who are not able to solve the problems using mental math. Elaborate that it's okay to need support!
- Model using the multiples of 10 scaffold to solve a few problems similar to what students will see in the game for students who need extra support prior to playing the first round of bingo.
- Get out a bag of the calling cards and play one round of bingo as a whole group.
- Have students play one or two rounds in their small groups, allowing students who were the callers to switch roles with a bingo player.

#### Additional EL adaptations

**Beginning**

- Provide students with access to a bilingual dictionary with corresponding visuals.
- Give students a partially filled out copy of the Glossary prior to the lesson with words in English and their home language (L1).
- Research a video that demonstrates counting by 10's in the student's home language and play it for the class (if possible).
- Allow students to play Mental Math Bingo in a small, teacher-led group or with peers who speak the same home language (L1), if possible.
- Allow students to share their closing remarks in their home language (L1).

**Advanced**

- Encourage students to explain their ideas and thoughts throughout the lesson without referring to the sentence stems/frames for support.
- Ask students to explain what mental math means to the class.
- Challenge students to think of one or two different types of mathematical problems they can solve using mental math.

#### Assessment

- Rotate around the classroom and observe students as they play. Make note of students who are able to solve the addition and subtraction problems mentally, and students who refer to the table on the top of their worksheet for support.

#### Review and closing

*(3 minutes)*

- Bring students together as a whole group. Write the following sentence stems/frames on the board and have students share their ideas with a partner:
- Mental math was
**____**(easy/okay/difficult) for me because**____**. - I used
**____**(insert strategy) to solve the problems instead of mental math. - I'm still wondering about
**____**.

- Mental math was