Marshmallow Tower

Have a race to see who can build the tallest and strongest tower out of marshmallows and toothpicks! This is sure to get the kids excited while learning about structural engineering! Our kids loved building (and eating) these towers. We learned the basics about structural engineering and how to make a stable marshmallow tower!

Marshmallow Tower Lesson Plan

Objective-

To have a better understanding of how structures are built and what makes a strong building.

Materials

• Bag of Marshmallows (we used one bag for 4 structures.)
• Box of toothpicks (we used one box of 800, this was plenty for 4 structures.

A Few Points to Decide Beforehand

There are a few ways to do this lesson. Think through which variation will work best for your purposes and group.

• You can have the teaching discussion before actually building the tower. This way the kids know and understand the basics and can use what they learned while they build. Then build one tower.
• You can build a tower with no previous understanding. Then have the discussion, learn what might have helped to make a stronger tower and then build a second tower using the skills you just learned.
• You can build first, have the kids experiment and then explain what they should have done. This may just leave them, wanting to try again.

You can also choose different variations

• Limit the supplies- each kid gets a limited number of marshmallows and toothpicks.
• Limit the time- put a time limit on the building process. The kids only get 15 minutes (or similar) to build.
• Build individually- this works best in a home setting or with fewer kids.
• Build in teams- this would work best in a classroom setting or with more kids.

Lesson Discussion

We are going to learn how to build strong towers today.

We are going to use toothpicks and marshmallows to try and build the tallest tower possible.

Making Predictions-

Are the toothpicks going to be stronger if they are going vertically or horizontally? Answer: Vertical is stronger. Demonstrate by putting pressure on a horizontal toothpick and watching it bend. Then put pressure on the vertical toothpick, it doesn’t bend.

Will the toothpicks be stronger with 1 toothpick or 3? Answer: 3 Demonstrate: Take one toothpick and let a child break it, then take 3 toothpicks and try to break them. Which was harder?

Which shape is the strongest? (Triangle, square, pentagon) Answer: the triangle is the strongest.

What will make the base the most stable? Answer: Having a larger base and then becoming more narrow as you move up will be the strongest. Like a pyramid.

What is the weakest point? Answer: the joints. Demonstrate by building a square with two toothpicks and two marshmallows. Put pressure on the toothpicks and watch how the marshmallows break. The joints are the weakest. The fewer the joints the stronger the structure.

The fewer joints a structure has the stronger it is. What structure has no joints and would be stronger than a triangle? Answer: a circle.

The base has to support the weight of the entire tower.

Experiment

Decide if you are giving limited time or resources. Tell the kids the parameters that they have (time, resources, teams or individually building.)

The goal is to build the tallest tower possible.

Divide up the supplies and begin.

Talk about what you see as you build. For us, two of the kids started with a small base. One started with a large base. We were able to compare the differences as they built. This really helped them learn and see the principles we had talked about during the discussion.

After the time is up, measure the towers and see how everyone did.

Conclusion

What did you learn about your structure as you built it?

What turned our differently than you expected?

What went the same as you expected?

If you were to do this again a second time, what would you change?

We hope you loved this marshmallow tower experiment! Check out our other lesson plans. We loved learning about chemical reactions with this kid friendly elephant toothpaste lesson!