## Lesson: Expressions and Equations

Introducing the Concept

Without realizing it, your students simplified expressions and solved equations when they were asked to add and subtract given numbers. They probably didn't know that 5 + 3 is an expression and that 7 + 2 = 9 is an equation. It is important for students to understand these terms in order for them to clearly understand the similarities and differences between equations and expressions. They will begin to use algebraic expressions that feature variables as well. By employing their addition and subtraction skills, they will be simplifying expressions and evaluating algebraic expressions. Stress the progression from an expression to an equation by demonstrating how equal expressions are found on either side of an equals sign.

**Materials:** overhead projector or chalkboard

**Preparation:** none

**Prerequisite Skills and Concepts:** Students should have a working knowledge of addition and subtraction.

Write **5 + 3** and **5 + 3 = 8** on the board or overhead. Have a student read aloud the expression **5 + 3** and the equation **5 + 3 = 8**.