## Description

# What our Evaluate Expressions lesson plan includes

Lesson Objectives and Overview: Evaluate Expressions details how to solve mathematical equations when a variable can be substituted with an actual value. The lesson also reminds students to use the correct order of operations to solve the problems once they replace the variables with numbers. Relevant vocabulary, like simplify and substitute, is included in the lesson. At the end of the lesson, students will be able to write, read, and evaluate expressions in which letters stand for numbers. This lesson is for students in 4th grade, 5th grade, and 6th grade.

**Classroom Procedure**

Every lesson plan provides you with a classroom procedure page that outlines a step-by-step guide to follow. You do not have to follow the guide exactly. The guide helps you organize the lesson and details when to hand out worksheets. It also lists information in the blue box that you might find useful. You will find the lesson objectives, state standards, and number of class sessions the lesson should take to complete in this area. In addition, it describes the supplies you will need as well as what and how you need to prepare beforehand.

**Options for Lesson**

Included with this lesson is an “Options for Lesson” section that lists a number of suggestions for activities to add to the lesson or substitutions for the ones already in the lesson. One optional addition to the lesson activity is to increase the number of rounds for the students and make new cards with advanced problems for groups of students that may be done quickly (this is also an excellent way to differentiate the lesson for all levels of learners). For an additional activity, you could have your students use white boards to solve problems where they can ‘erase’ the variable easily and substitute in a value.

**Teacher Notes**

The teacher notes page includes lines that you can use to add your own notes as you’re preparing for this lesson.

**EVALUATE EXPRESSIONS LESSON PLAN CONTENT PAGES**

**Evaluating Expressions**

The Evaluate Expressions lesson plan includes two content pages. When you replace one thing with another, we call that substitution. For example, if your teacher is sick and cannot come teach your class, you will have a substitute teacher. They are replacing your teacher. In math, we use substitution when we replace a variable in an expression with an actual value.

Once we replace the variable, we can evaluate the expression. This means that we will substitute each variable for a number and solve using arithmetic operations. For example, we might have the equation 4z + 6 – 8 + z and are told that z = 2.

To solve, we first need to rewrite the expression will empty parentheses where each variable will go: 4( ) + 6 – 8 + ( ). We can then substitute the values easily: 4( 2 ) + 6 – 8 + ( 2 ). We substituted the number 2 for every “z” in the problem, because z = 2. Next, we solve the problem using the order of operations. 8 + 6 – 8 + 2 = 14 – 8 + 2 = 6 + 2 = 8. Therefore, when z = 2, the expression has a value of 8.

However, what if z = 7? Instead of substituting a 2 inside each parenthesis, we substitute a 7: 4( 7 ) + 6 – 8 + ( 7 ). Then, we solve using the order of operations: 28 + 6 – 8 + 7 = 34 – 8 + 7 = 26 + 7 = 35. When z = 7, the expression has a value of 35.

The lesson includes some more examples, including one with multiple variables. To solve, we follow the same steps, we just substitute numbers in for more than one variable.

### Vocabulary Recap

The lesson closes with a quick vocabulary recap. To simplify means to perform any indicated operations so the expression is in simplest form (the least number of terms and no parenthesis). To evaluate is to find the value of an expression by replacing variables with a number. Next, substitute means to replace the variable with parenthesis ( ) first, then substitute the number for the variable in the parenthesis and simplify. Finally, a solution is the replacement for the variable which makes the sentence true.

**EVALUATE EXPRESSIONS**** LESSON PLAN WORKSHEETS**

The Evaluate Expressions lesson plan includes three worksheets: an activity worksheet, a practice worksheet, and a homework assignment. You can refer to the guide on the classroom procedure page to determine when to hand out each worksheet.

**CARDS ACTIVITY WORKSHEET**

Students will work in groups of three to complete the lesson activity. Each student in the group will be assigned the letter A, B, or C. Each group will receive a set of cards and students will work individually to solve the answer for their letter. The group will then add all three answers for a final total.

**DIFFERENT VALUES PRACTICE WORKSHEET**

For the practice worksheet, students will evaluate 10 expressions using the values shown in the box on the worksheet.

**EVALUATE EXPRESSIONS ****HOMEWORK ASSIGNMENT**

The homework assignment asks students to evaluate each expression for the given values of each variable.

### QUIZ

This lesson also includes a quiz that you can use to test students’ understanding of the lesson material. For the quiz, students will

**Worksheet Answer Keys**

This lesson plan includes answer keys for the activity worksheet, the practice worksheet, the homework assignment, and the quiz. If you choose to administer the lesson pages to your students via PDF, you will need to save a new file that omits these pages. Otherwise, you can simply print out the applicable pages and keep these as reference for yourself when grading assignments.