Lesson objective: Understand that shapes may share some attributes with other shapes in different categories.

This lesson provides an opportunity for students to apply their knowledge and understanding of common attributes to a mathematical situation. Students are asked to assess whether a shape fits into a category based on the attributes of the shape.

Key Concept students will use:

- all rhombuses, rectangles and squares are examples of quadrilaterals, but not all quadrilaterals fit in those subcategories

Skills students will use:

- reasoning with shapes and their attributes; (Grade 2, Unit 10)
- recognizing and drawing shapes with specified attributes, such as a given number of angles or a given number of equal faces; (Grade 2, Unit 10)
- identifying triangles, quadrilaterals, pentagons, hexagons, and cubes; (Grade 2, unit 10)

Students engage in Mathematical Practice 7 (look for and make use of structure) as they determine categories and subcategories of shapes by identifying and reasoning about their attributes.

**Key vocabulary: **

- attribute
- quadrilateral
- pentagon
- triangle
- parallel

**Special materials needed:**

- index card or other tool for measuring right angles