Monday, April 15, 2013

Shapes, Letters, & Towers: Building with Marshmallows

You know what I love even more than when an activity goes exactly as planned? When my kids take the lesson even further than I'd dreamed. That sends this deceptively educational mom over the moon!

This simple engineering activity is a perfect example.

I got the idea from a local STEM event eons ago, that provided kids with mostly edible building supplies and asked them to build and evaluate which shapes created the strongest, most stable structure. On the table were gumdrops, marshmallows, toothpicks, and uncooked spaghetti noodles.

For our experiment, I omitted the gumdrops. Marshmallows would suffice as our "connectors."

I started by asking my oldest son to build a cube with toothpicks and marshmallows. What he soon discovered was that it was wobbly, wonky, leaning, and shaky (choose whichever adjective you like best).

To stabilize it, he added diagonal lengths of broken spaghetti noodles (essentially X shapes around all the sides). We checked the cube; no more wobbling! He was excited. Now the pace of building REALLY picked up.

While he was busy popping marshmallows in his mouth and building his four-story tower, little brother came wandering by.

"I want to do that," said my preschooler. "I want to make a triangle."

This was when the questions came spilling out of my mouth. "How many sides does a triangle have? How many toothpicks will we need?" In no time flat, he was exercising his fine motor skills to make a triangle.

"I want to make an E," he said next. This took a little more instruction from me but boy, oh boy, was he proud when we were done.

What started as an engineering activity for my oldest son became that AND a lesson in shape and letter recognition for my youngest son. That made the nominal amount I spent on supplies for this activity WELL worth it!


  1. This is wonderful! I did a similar activity in my kindergarten class recently, with one added challenge. I asked them to build a structure that would support the most weight. We then put a shallow cup on top of the structure, and added weight (in the form of plastic bears), one at a time. It was a great way to assess engineering, and then redesign to make things stronger. So fun!

    Teaching Ace Blog

  2. This is such a great post! My nine year old son wants to do something like this for his science project, and he's taken it upon himself to find the coolest structure known to man kind. We've been doing a little bit of research about what to build, what materials we could use to make it stronger, and how to build the structure so that it will maintain it's shape. It's actually been a lot of fun, and an interesting journey all at the same time. I'm enjoying it while I can though. My son won't be building tooth pick and marshmallow bridges forever. :)

    Telar Co