# Lesson 7

Rectangles and Squares

### Lesson Purpose

The purpose of this lesson is for students to understand that a square is also a rectangle.

### Lesson Narrative

The purpose of this lesson is to establish a hierarchy of quadrilaterals based on properties of angles and side lengths and to represent that hierarchy using a diagram.  Students examine the relationships between different pairs of quadrilaterals, notably squares and rectangles but also squares and rhombuses, and trapezoids and parallelograms. They have worked with explicit examples of these shapes in previous lessons and described their defining attributes. In this lesson they put all of these relationships together to understand relationships between categories (MP7), such as:

• A quadrilateral that is both a rectangle and a rhombus is a square.
• Rhombuses, squares, and rectangles are all parallelograms, but parallelograms don't have to be rhombuses, rectangles, or squares.

Students should have access to straight edges, protractors, and patty paper throughout this lesson.

• Action and Expression
• MLR8

### Learning Goals

Teacher Facing

• Explain why a square is also a rectangle.

### Required Materials

Materials to Copy

### Required Preparation

Activity 1:

• Create a set of cards from the blackline master for each group of 2.
• Gather diagram from a previous lesson.

Building Towards

### Lesson Timeline

 Warm-up 10 min Activity 1 15 min Activity 2 20 min Lesson Synthesis 10 min Cool-down 5 min

### Teacher Reflection Questions

As students shared their ideas today, how did you ensure all students’ voices were heard and valued as an important part of the collective learning?