The Greedy Triangle. Written by Marilyn Burns. Mrs. Campbell First Grade. Materials. The book The Greedy Triangle. Crayons. Shape Book. Pencils. Geoboard. Smartboard. Whiteboard. Introduction.
Written by Marilyn Burns
Mrs. Campbell First Grade
This story is about a Triangle who wants to be more than just a Triangle. It believes that more angles and corners will make life better. So the Triangle visits the character the Shapeshifter. The Shapeshifter changes the Triangle into many different shapes.
Do you think some shapes are better than others and why?
How will the Shapeshifter change the Triangle into different shapes?
What shapes do you think the Triangle will turn into?
Sides- Sides are the outside lines of a shape.
Corner- a corner is where the sides of the lines meet.
The next set of vocabulary words I will introduce
are quadrilateral, pentagon, and hexagon.
A quadrilateral has four sides and four corners. A baseball diamond is the shape of a quadrilateral.
A pentagon has five sides and five corners. A
soccer ball is made up of tiny pentagon shapes.
A hexagon has six sides and six corners. A
Bee hive cell is the shape of a hexagon.
A hexagon is a seven sided shape with seven corners. A flower can be in the shape of a hexagon.
An octagon is an eight sided shape with eight
corners. A stop sign is the shape of an
A nonagon is a nine sided shape with nine
corners. The top of a building can be in the
shape of a nonagon.
A decagon is a ten sided shape with ten
corners. A mirror can be in the shape of a
Let’s have some fun reviewing our shapes.
What is the lesson the triangle learned?
What is the lesson you learned?
Let’s have some fun watching a video about shapes and sizes.
You are going to become a shape detective. Your new assignment is to go home and cut out five pictures of different shapes from magazines, newspapers, food boxes and construction paper. You will bring the pictures to school and create your very own shape book. Have fun being a shape detective!
Burns, M. (1994). The Greedy Triangle. New York: Scholastic.
Other Marilyn Burns Books
Wonderful Article Written By Marilyn Burns: Connecting Writing and Math
My school does not have computer time for first graders however, there is a portable smartboard. I will be using the smartboard to teach this cyber lesson in a whole group setting over the course of a week.
Cyber Lesson- Slide 4: I will have the students brainstorm a list of familiar geometric shapes on the smartboard. Then I will have the students draw pictures of the shapes they predict the triangle will turn into on their own whiteboards. Next I will introduce vocabulary words that the students will hear throughout the story.
Cyber Lesson- Slide 4: Then after I introduce these vocabulary words I will have the students find an object in the classroom that is a triangle. Then I will ask the students to point to the sides and angles of the object.
Cyber Lesson- Slide 6: To not overwhelm the students with challenging vocabulary I will address new words when they are mentioned in the story.
Cyber Lesson- Slide 7: While reading the book The Greedy TriangleI will stop periodically to have the students predict how many sides and angles each new shape will have. Then they will record their answers on their own whiteboard. Lastly, I will confirm their predictions on the smartboard by having the correct answer appear on my chart.
Cyber Lesson- Slide 8: When I finish reading the story the students will return to their seats and get a geoboard. They will be creating the different shapes from the story The Greedy Triangle. They will be making the same shapes as Mrs. Campbell makes on her geoboard. To check their work I will encourage the students to count the sides and angles of their shapes. The students will be making these shapes: triangle, quadrilateral, pentagon, and hexagon.
Cyber Lesson- Slide 8: When the students have finished making all of the shapes I will redirect their attention towards the theme of being greedy. I will remind them that a three sided shape is just as important as a shape with more than three sides.