Lesson objective: Understand that an expression doesn't have to be equal to another. It can be less than or greater than another.

Students bring prior knowledge of inequalities from 6.EE.B.7. This prior knowledge is extended to algebraic expressions as students compare expressions. A conceptual challenge students may encounter is the concept that changing the value of a variable can change the relationship of two expressions.

The concept is developed through work with number lines, which will help students to visualize the relationship between the expressions.

This work helps students deepen their understanding of numbers because they will need to substitute multiple numbers into the expressions to evaluate the relationships formed.

Students engage in Mathematical Practice 2 (Reason abstractly and quantitatively) as they evaluate the relationship between two algebraic expressions for different values of the variable.

**Key vocabulary:**

- expression
- greater than
- less than
- value