The Greedy Triangle
📝 This post, The Greedy Triangle, was originally published in 2014 and has been updated with new information and resources.
Looking for an engaging geometry read-aloud for kids? The Greedy Triangle by Marilyn Burns is one of my favorite math picture books for teaching shapes, sides, angles, and attributes in a fun and memorable way. Pair this beloved story with a free writing activity to extend learning and encourage creative thinking in your classroom.
Why Kids Love The Greedy Triangle
Students love The Greedy Triangle because the story is imaginative, funny, and interactive. As Triangle transforms into shapes with more and more sides, students become excited to predict what shape will come next. The story makes geometry concepts memorable and fun while encouraging creativity and discussion.
The Greedy Triangle
Triangle is tired of being a triangle, so he visits a shapeshifter who magically turns him into new shapes with more and more sides and angles. But after becoming quadrilaterals, pentagons, and beyond, Triangle discovers that sometimes being yourself is best after all. What a creative and memorable way to teach geometry concepts to young learners!
The video version of The Greedy Triangle is available here.
What Students Learn From The Greedy Triangle
✔️ names of 2D shapes
✔️ sides and vertices
✔️ geometry vocabulary
✔️ shape attributes
✔️ creative thinking
✔️ writing with “because”
After reading and discussing the story, it was my students’ turn to create their own shape-inspired writing pieces.
Free Shape Writing Activity
I introduced this FREE template to the group, modeled how to use it, and then set them to work. I also encouraged students to explain their thinking by adding a “because” to their writing.
Here are some examples from my students.
Looking for More Shape Activities?
💚 Looking for more engaging math read-alouds and shape activities? Be sure to check out the posts below for more geometry fun and free printables!
The Shape Trilogy Shape Response Activities with FREE Templates
The Best Books about Shapes with Extension Activities
💚 What shapes will your students choose to write about after reading The Greedy Triangle?
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Great ideas! We loved this book when daughter was younger!
So many fun math activities, I need to read this story, I had forgotten about it and I think my girls would love it. Wishing you a very Happy Thanksgiving Stephanie. So thankful for you as part of our after school team!
Thank you Kim!! I love this group and am so thankful to be a part of it!! Happy Thanksgiving to you too!