# Express Yourself!

• Math
• 65 minutes
• Standards: 5.OA.A.2
• no ratings yet
July 28, 2015

Help your students create a basis for future math classes with this lesson that teaches children about math expressions and how they can interpret them.

### Learning Objectives

Students will interpret numerical expressions without solving them and write simple expressions.

## Lesson

### Introduction (5 minutes)

• Review the commutative property of multiplication and the order of operations.
• Teach students that expressions are a series of numbers and symbols, such as +, -, x, and ÷, without an equal sign.
• Write the expression 5 (4 + 3) on the board.
• Tell students that when that expression is worked out it is called an evaluation of the expression.
• The expression equals 35, therefore 5 (4 + 3)= 35 is the equation.
• Tell students that the expression 5 (4 + 3) is 5 times larger than the expression (4 + 3).
• Let students know that today they are going to evaluate the relationship between expressions and write their own expressions to evaluate.

### Explicit Instruction/Teacher Modeling (10 minutes)

• Write the steps “double five and then add 50” on the board.
• Ask students to write an expression for the steps above.
• They should write (5 x 2) + 50 or 5+5+50.
• Write the expression "6 (10x10)" on the board.
• Ask students to describe, in writing, how the expression relates to (10x10).
• They should write that the expression 6 (10x10) is 6 times larger than the expression (10x10).
• Choose volunteers to create their own expressions like the two you just modeled and explain them.
• Guide students through the process of evaluating their expressions orally.

### Guided Practice/Interactive Modeling (10 minutes)

• Allow students to form pairs or small groups.
• Pass out the Welcome to Mummy’s Market worksheet.
• Advise students that they should work with a partner or group to write an expression and evaluate the expressions.
• Remind students to refer back to their notes from the models you provided.

### Independent Working Time (20 minutes)

• Pass out blank paper.
• Tell students that they are going to work alone to create their own expressions and evaluate the relationships between the numbers just like they have been practicing.
• Students may need an example to get them started. Example: Write an expression in words, such as "divide 144 by 12, and then subtract 20." Students should write (144 ÷ 12) – 20 and go on to write that the expression (144 ÷ 12) – 20 is 20 less than (144 ÷ 12).

## Extend

### Differentiation

• Enrichment: Advanced students can evaluate expressions that contain fractions, decimals, etc.
• Support: Struggling students can use the Multiply It! worksheet during the guided practice.

## Review

### Assessment (15 minutes)

• Pass out the Express Yourself assessment.
• Advise students to use a blank sheet of paper to show their work.
• Remind them that they must follow the directions and answer the questions completely.

### Review and Closing (5 minutes)

• Write the following expression on the board: (200 ÷ 10) x 0.5.
• Have students identify the expressions and equation.
• Then have students evaluate the expression without calculating it: (200 ÷ 10) x 0.5 is ½ of (200 ÷ 10).
• Ensure that students can create a word problem or steps for this equation: divide 200 by 10 then multiply by a half.