# Cutting Corners

Purpose

This is a Level 3 Geometry activity from the Figure It Out Series.
A PDF of the student activity is included.

Achievement Objectives
GM3-3: Classify plane shapes and prisms by their spatial features.
Student Activity

Click on the image to enlarge it. Click again to close. Download PDF (161 KB)

Specific Learning Outcomes

identify three dimensional shapes.

Required Resource Materials
cardboard circles, rectangles, and triangles

rubber bands or string

FIO, Level 2-3, Geometry, Cutting Corner, page 24

model spheres, cylinders, and cones

Activity

“Solids of revolution” are created when a flat (two-dimensional) shape is rotated about an axis.

#### Activity One

As the circle turns, its rotational image is a sphere, like the shape of a basketball or a planet.

#### Activity Two

The rotational image of a rectangle is a cylinder.

#### Activity Three

The rotational image of the triangle is a cone.

Students may wish to investigate the rotational images of other shapes, such as:

Some examples of solids of revolution are woodturning on a lathe and figure skating.

Activity One
1. A sphere
2. The list could include balls, marbles, soaps, parts
of buildings, poi, and oranges.

Activity Two
1. A cylinder
2. The list could include paper rolls, tins, jars,
poles, and tubes.

Activity Three
1. A cone
2. The list could include ice-cream cones, traffic
cones, and turrets.

Attachments