# There Must Be Order!

Help your students understand PEMDAS and its importance with this lesson that gives them practice with parentheses, braces, and brackets.

#### Learning Objectives

Students will evaluate numerical expressions that use parentheses, brackets, or braces.

#### Introduction

(10 minutes)
• Have students write "PEMDAS" across the top of their papers. Have them write the meaning behind each letter of the acronym next to, on top of, or below each letter.
• Tell students that they will use this as a checklist when they solve equations. Students may need your help to get started.
• Give students a simple mathematical expression like (25–11)x3.
• Ask students to start with the letter “P” and first work the expression in parenthesis:(25–11) x 3 = 14x3.
• Then ask students if they can identify any Es. They should say no.
• Ask them to solve any Ms: 14x3 = 42
• Next, ask them are there any Ds, As, or Ss? They should say no.
• Advise them that they just used the order of operations to solve this expression.
• Explain that today’s lesson is going to require them to use the order of operations to solve mathematical equations that have parenthesis, braces, and brackets which are tools used in math to group equations.