STEM activities are a lot of fun and educational, but the best kind of STEM activities are open-ended, allowing children to think for themselves. In this marshmallow shape towers STEM challenge, kids are challenged to make a marshmallow tower, but not only make a tower, but to make a tower using specific shapes. They must follow all elements of a real design process, including brainstorming, blueprints, prototypes, tweaking, and testing their designs.

This fun twist on the classic marshmallow structures asks kids to go to a new level of creativity and only use specific shapes for their marshmallow towers. #stem #handsonlearning #scienceactivities #handsonscience

Marshmallow Shape Towers STEM Challenge

You need a few supplies for this challenge:

  • Marshmallows (use big or little for different effects)
  • Toothpicks (colored ones are more fun)
  • Examples of shapes to try

Tell the kids they must construct a marshmallow tower, but only from specific 3D shapes. This becomes tricky the instant you start adding levels to your towers!

For a greater challenge, give each child a specific shape they must build with. One might be only able to build with triangles, while another, octagons. It’s your choice to decide if the kids must use 3D shapes or can use flat shapes to complete their towers.

What designs worked best? What designs were not as good? What were the best parts and worst parts of each design? How could the kids improve on them in the future?

Marshmallow Shape Towers STEM Challenge Explained

The thing that makes this shape tower more challenging is that the kids must use specific shapes in their designs. It gets pretty tricky to stack marshmallows when they must be in a specific shape and pattern. One fun variation on this activity is to vary the size of the marshmallows, which makes the experiment both a bit easier in some ways and harder in others. The more marshmallows you have, the more elaborate the structures can be!
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Colleen Kessler

Colleen is an explorer, tinkerer, educator, writer, creator, and a passionate advocate for the needs of gifted and twice-exceptional children. She has a B.S. in elementary education, a M.Ed. in gifted studies, is a sought-after national speaker and educational consultant, and is the founder of the popular blog and podcast Raising Lifelong Learners, as well as Raising Poppies, a community of support for parents of gifted children. She lives in northeast Ohio with her four bright and quirky kiddos, patient husband, and ever-changing collection of small reptiles, mammals, and insects.

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