Toothpick Bridge -- STEM Project

For another smooth integration for your science and math curriculum, this 21st Century Math Project intends to bridge that gap. Hahaha get it? Bridge the gap! And it's a project about Bridges! You get it? Contest style, students will try to build the strongest bridge as light as possible. 

Name: Toothpick Bridge

Take that toothpick out of your mouth and build a bridge
with it!

Suggested Grade Level: 7-12 (Geometry skills)

Math Concepts: Measurement, Shapes, Symmetry

Interdisciplinary Connections: Engineering, Science, Architecture

Teaching Duration: 4-5 Days (can be modified)

Cost: $5 for a 12 Page PDF (1 project, 1 assignment and handouts) 

PDF Version: Toothpick Bridge @ TPT

The Product: Students create presentations regarding their design process and the links to geometry. Oh, and of course an awesome contest.

What's all that noise?! Student
Engagement?!! Bah!!

One of my favorite high school memories was doing this type of project in Physics. I seemed to have a glue problem -- meaning that I used WAY too much glue. I still contend that the bridge didn't break, but kind of folded. So while I certainly did not invent this project, I thought the applications to geometry were really strong. Each type of design has elements of geometry built in.

Break stuff? I'm in.

In this project, teams of up to three students will construct a bridge out of only toothpicks. This toothpick bridge must be able to hold a predetermined load without failing. Teams will research the style of bridges, create a three-view diagram of a bridge, build it, test it and complete a presentation about the project and its connection to geometry and the design process. The ultimate goal is to build a bridge that is strong, but is light as possible. The bridge with the greatest ratio of load weight to bridge weight will win the contest.

I limit students to only using flat toothpicks and Elmer's glue. I find the simpler, the easier. 

As far as testing these bridges go some people like to stack free weights. In high school, I recall this falling on someone's foot so I didn't do this. I've seen a string connecting a bucket to a 2x4, but that would require having a drill press handy. I've chosen to write the project using a good ol' fashion bungee cord and a large bucket (think a 5 gallon paint can). I like to write these in a way anyone can pull them off with minimal complications. 

Who needs a consultation?

In the bucket, I fill it with water and use a household scale to determine the winner. Of course, you'll need to borrow a gram scale to measure the weight of the bridge. While it is a little bit of hunting, the payoff promises to be a blast and one that high school students will not forget.

EXTENSION: You could attach a budget to this project! Maybe charging for toothpicks and cups of glue. Maybe charge for an engineering consultation. The possibilities are endless. 

It seems around every corner there's a new STEM school popping up and 21st Century Math Projects can help! If this is interesting I've also integrated projects for an Egg Drop, Box Car Derby and Solar Oven.