Curated OER
Exploring Polygons and The Greedy Triangle
Excellent lesson! Anne Linehane's geometry story, The Greedy Triangle, offers an opportunity to practice forming various types of polygons with your learners. Using elastic bands (or Chinese jump ropes), partners form the various shapes...
Curated OER
The Greedy Triangle-Intro to Geometric Shapes
In this geometry lesson, learners read The Greedy Triangle and use geoboards to construct geometric shapes. They identify the number of sides and angles each shape has.
National Security Agency
Classifying Triangles
Building on young mathematicians' prior knowledge of three-sided shapes, this lesson series explores the defining characteristics of different types of triangles. Starting with a shared reading of the children's book The Greedy Triangle,...
Utah Education Network (UEN)
Geo Shapes
Invite your first graders to compose and decompose two and three-dimensional figures with this fun, hands-on lesson. They investigate and predict the results of putting together and taking apart two-dimensional shapes with rubber bands...
Curated OER
Geo Shapes
First graders listen as the book, "Try It With Triangles" is read to the class. They name the geometric shapes that they see in the story and view the Shape Vocabulary Cards as they name them from the book. They then cut out the...
Curated OER
Triangles
Third graders recognize geometric shapes with acute angles, make geometric shapes with acute angles on geoboards, and draw acute angles on geopaper.
Curated OER
"The Greedy Triangle" by Marilyn Burns
Students review angles, sides, and properties of basic shapes. Using a geoboard, they make as many different tirangles as possible.
Curated OER
Using R&R to Teach Mathematics
Second graders create a shape garden. In this polygons lesson, 2nd graders practice making shapes using a geoboard and read the book The Greedy Triangle by Marilyn Burns. Students also design a shape garden using construction paper.
Curated OER
Tri this Angle!
First graders draw and describe various types of polygons. they investigate their own environments for examples of polygons. After reading the book, The Greedy Triangle, they discuss everyday objects that are polygons. They create shape...
Curated OER
Obtuse Angles
Third graders recognize and identify geometric shapes, work with manipulatives to reinforce understanding, and create polygons with various angles to display their knowledge of the different types of angles.