The Big Marshmallow Tower STEM Challenge

A couple of years ago, I had the opportunity to go into a local private school and work with some pretty amazing kids. I spent most of the afternoon with a class of fourth and fifth-grade girls and a class of eighth-grade boys. Both classes had fun putting their geometry and engineering skills to the test. Their mission-- to build structurally sound towers out of nothing but marshmallows and spaghetti noodles!

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About the Challenge

The Big Marshmallow Tower Challenge is a favorite math and engineering STEM activity for teachers and students around the world. The objective of this challenge is for students to apply their knowledge of geometry to design and build structurally sound towers using nothing but marshmallows and dried spaghetti noodles. 

Materials Needed

Very few materials are needed for this challenge and can be purchased inexpensively at a dollar store. You will need:

• boxes of dried spaghetti noodles 
• boxes of toothpicks
• bags of normal-sized marshmallows
• bags of mini marshmallows

Step One: Review Geometry Concepts and Vocabulary

To get the students into the mindset they need for this challenge, we went through a quick review of the basic geometric concepts:

• squares, cubes, triangles, pyramids, rectangular prisms
• angles, edges, faces, vertexes

Each student took a handful of toothpicks and mini marshmallows to build the basic 3D shapes. Then we had a quick discussion about which of these shapes had the most stability and which shapes have no support at all. The students concluded that triangles and pyramids are the most stable because they have fewer angles.

The students used toothpicks and mini marshmallows to construct a cube, pyramid, and rectangular prism.

Step Two: Use Geometry and Engineering to Build a Tower

The actual challenge itself is relatively easy. There is nothing for the teacher to prepare:

• Students can work independently or in pairs.
• Assign the students to different areas of the room to build their towers and give them some marshmallows and spaghetti noodles.
• Explain the objective to the students... to build a tower as large and as tall as they can, making sure it is structurally sound.
• Then, every so often, walk around and tap each tower. If the towers wobble or fall down, ask the students how they can improve their towers. Review angles and three-dimensional shapes as needed.

These two girls are working together to build their tower.

These girls are using pyramid-like angles to build their tower.

One of the boys broke his spaghetti noodles into smaller pieces to make his tower stronger.

When the students were finished building their towers, only one student wanted to take his tower home. The rest of the students decided to smash their towers. Deconstruction can be as much fun as construction!

Did you enjoy this post about this Marshmallow STEM activity? If so, check out these blog posts for more STEM and science activities:

• Pumpkin Life Cycle STEM Activity
• Pepper and Soap STEM Experiment
• How to Make a Mummy STEM Activity
• How to Grow Celery from Scraps + STEM Activity
• What Happens If You Don't Brush Your Teeth? STEM Experiment
• Hot Chocolate Surprise + STEM Activity

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