### Lesson plan

# GEMDAS: Order of Operations

#### Learning Objectives

Students will evaluate expressions with parentheses, brackets, or braces in numerical expressions.

#### Introduction

*(5 minutes)*

- Review PEMDAS as an acronym for order of operations.
- Write an expression on the board that includes parenthesis only.
*Example: 60 – 4 x (7 -2) + 23 + 32* - Discuss the rules that must be followed and evaluate the expression.
- Rewrite the expression on the board.
- Explain to students that brackets, braces, and other symbols are often used in mathematical expressions as well.
- Have students insert other grouping symbols to this expression.
- Discuss the similarities and differences in the problems.
- Explain that in today’s lesson, they will use a new and more accurate acronym, GEMDAS, to solve problems that have grouping symbols.

#### Explicit Instruction/Teacher modeling

*(5 minutes)*

- Write an expression on the board.
**Example: 60 – {[4 x (7 -2)] + 23} + 32** - Use the GEMDAS acronym to work through the expression.
- Reveal the correct answer.
- Have students create a second expression.
- Use GEMDAS to work through their expression.
- Answer any questions that students have.

#### Guided practise

*(10 minutes)*

- Using the GEMDAS Guided practise worksheet, have students work in small groups or pairs to solve the expressions.
- Have the students follow the acronym GEMDAS as they work through each of the sections until they solve the expressions.
- Use the key to check if students have the correct answers.
- Guide students who need additional help.

#### Independent working time

*(25 minutes)*

- Using the GEMDAS Independent practise worksheet have students use the order of operations acronym, GEMDAS, to work through each of the problems.
- Remind students that this activity is to be completed alone.
- Tell students to follow the order according to GEMDAS.
- Use the key to check student answers.

#### Differentiation

**Enrichment:**Allow students to create their own problems and solve them.**Support:**Have students create a GEMDAS foldable that they can use as they work through each problem.

#### Assessment

*(5 minutes)*

- Have students identify the GEMDAS components.
- Have students write the following expression on an exit ticket: {[(5 x 6) ÷ (12 x 3)] – 8} + 4
- Have each student solve the expression and turn it in for a quick assessment.
- If time permits, allow students to solve the expression using the interactive whiteboard.

#### Review and closing

*(5 minutes)*

- Recap today’s lesson.
- Remind students that PEMDAS and GEMDAS are both common acronyms used for remembering the order of operations.
- Allow students to ask questions that they still have and make comments about what they have learned.