A Lesson Plan for The Greedy Triangle

Theme: Polygons

NCTM Standards:
Pre-K–2 Expectations
In prekindergarten through grade 2 all students should: recognize, name, build, draw, compare, and sort two- and three-dimensional shapes; describe attributes and parts of two- and three-dimensional shapes.

Teacher Notes
A polygon is a two dimensional shape (a shape in a plane) that has straight sides. Polygons have height and length but no depth.

Lesson Plan
The goal of this lesson is learning the names of polygons.

You will need:
A copy of The Greedy Triangle by Marilyn Burns; geo boards and geo bands (rubber bands); graph paper, straight edges and pencils for each child

New words:
Polygon; triangle; square; pentagon; hexagon

Review
Ask children to name the shapes they know and talk about the different characteristics of each shape. E.g. A triangle has how many sides? A square?

Anticipatory Set and Objective
Tell children to listen for the names of the different shapes as you read the story because you will ask them to repeat them. Ask them to remember what each shape looks like.

Read the Book.

Ask “What were some shapes in the story?”

Guided Practice
Draw a shape. Have the students make the shape that you make their geoboards.
Ask the students what the name of the shape is…hint: count the number of lines

Make 5-10 shapes depending on grade level.

Give students a chance to experiment with their shapes by giving them 5-10 minutes to play with the geoboard.

Check for Understanding
Discuss the names of shapes. Ask each student to name a shape and tell you the characteristics of that shape.

Independent Practice
Provide graph paper. Have students pair up. Ask each pair to draw a shape talked about in the book to hang the classroom for future reference and to label the shape.
Check each drawing for the correct amount of lines, straight lines, the name of the shape.