# Defining Proportional Relationships Lesson Plan Example for 7th Grade Students

## Topic: Defining Proportional Relationships

### Objectives & Outcomes

• Understand the concept of proportional relationships and how they can be represented using a graph.

### Materials

• Graph paper
• Markers or pencils
• Calculator (optional)

### Warm-up

• Ask students what they already know about proportional relationships. Write their responses on the board.
• Explore examples of proportional relationships using a graph, such as a graph of a line or a graph of a table. Ask students to explain how the graph represents the relationship between the two variables.

### Direct Instruction

• Explain that a proportional relationship is a relationship between two variables where the ratio of one variable to the other is constant. For example, if the ratio of x to y is 2:3, then x is proportional to y and their ratio is 2:3.
• Define the terms "constant" and "ratio" for students.
• Use the examples from the warm-up activity to illustrate these concepts.

### Guided Practice

• Provide students with a few more examples of proportional relationships, such as y = 2x and 3x + 4y = 15. Have them identify the constant ratio in each case and explain why the relationship is proportional.
• As a class, create a Venn diagram showing all the common elements in the examples provided.

### Independent Practice

• Have students choose one of the proportional relationships from the examples provided and use it to predict the value of another quantity. They should then test their prediction by calculating the value of the quantity in question.
• Encourage students to share their predictions and explanations with the class.

### Closure

• Review the main points of the lesson, including the difference between proportional and non-proportional relationships, and the process for calculating the value of a dependent quantity in a proportional relationship.
• Remind students of the importance of understanding proportional relationships in math and in the real world.

### Assessment

• Observe students during the independent practice activity to assess their understanding of the concept of a proportional relationship and their ability to calculate the value of a dependent quantity in a proportional relationship.
• Collect and review the charts and graphs students create as part of their independent practice activity.
• Administer a quiz or written assessment to evaluate students' understanding of defining and calculating the value of a dependent quantity in a proportional relationship.