Wednesday, May 16, 2012

Engineering a Bridge

After I attended a Mom’s Night Out for STEM (science, technology, engineering, and math) event, I realized that our afterschool curriculum was void of any engineering-related activities. I know what you’re thinking. Engineering for a six-year old?!?

My answer to that is … YES!

We read a fantastic book by Philemon Sturges that highlighted great bridges from around the world. Through the pictures and the words, we were able to take a trip across the globe and explore feats in bridge engineering. By far, the most impressive in the book was a bridge that holds water for boats to travel on. “Say what?!?” Yep, it’s absolutely real. Both my son and I had to pick our jaws up off the table.

Now, I grabbed some straws and paperclips. And we began building. The paperclips easily slipped into the ends of the straws and could be connected together.

It didn’t take long before we’d built the bottom and sides to a bridge. We added more straws to make the top and connected it all together.

Let’s just say, the bridge was a flop. I don’t mean a failure. I mean ... well ... floppy. My son and I were bummed.

our floppy bridge

Then I asked him, “What’s wrong with it? Let’s think like engineers.” And so it was that we decided to stabilize our bridge by reinforcing the paperclip joints with thin strips of duct tape.

Before we taped heavyweight cardstock to the bottom of the bridge (so my son’s Hot Wheels cars could drive over it), we added a few more straws as crossbars for extra support.

The bridge was a HUGE success. It was as much an exercise in engineering as it was problem solving. And my son L-O-V-E-D driving his cars over it. This activity was fun during and fun after – what could be better?!?

NOTE: I think I'll try to find straws that don't bend for our next bridge.


  1. Oooo- this would be a great project for my kiddos to try with their Wikki Sticks! Thank you for the inspiration!

    1. Good idea, Wonder Mom! I also thought it'd be fun to use the straws and paperclips for making various polygons.

  2. We did some engineering projects similar to this with my then 3-year old! Young kids love this sort of thing.

  3. This is awesome! I love the idea of using the paperclips in the straws! I see a ton of straws and paperclips in our very near future! My kids are gonna love this project!

    I'd like to invite you to link this (and any other projects/recipes you'd like) up on my first link party.
    Your readers are welcome, as well!
    I hope to see you all there! :-)

  4. You know, I've been trying to think of how to do projects like that, but hadn't really thought about paper clips for some reason.

  5. Since your blog is one of my favorites I have awarded you with the "One Lovely Blog" award!

    Head on over to my page to check it out: ThirdGradeIsAHoot

  6. Yep. I do this in my classroom and cut the ends off that have the bending element. Paper clips are good to use for joing, and actually pipe cleaners cut down to size are good, too. One lesson to learn is the MORE you fool with the paper clips (inserting/removing/etc.), the weaker the structure becomes. I love building w/straws!!

  7. Very cool. Triangles are way strong and way cool! I had one thought. Since January, my 1st grader and I have played around with building platonic solids(cube, tetrahedron, etc.). We've finally figured out that a full-length straw is not that sturdy and that a shorter straw makes a more solid/secure structure. We've had a lot of success recently with the ratio of 3" straw to 1/3 of a pipe cleaner (half in one straw, the other half in a connecting straw). That might help with the bending issue. :-)

  8. That looks so cool! My kids would love it!

  9. What a great idea to use paper clips with the straws. We've only ever used sticky tape. Will definitely try this with my sons. Thanks for sharing.

  10. What a brilliant idea and made with materials I have around the house

  11. This is VERY cool! and really, a bridge that holds water? Amazing!!!

  12. That a brilliantly executed bridge. The paperclip fastenings are genius!

    Thanks for sharing on Science Sparks.

    Kerry :)

  13. This is such a great activity for children. I remember spending one year with my son in SECME as he competed in a bridge building competition with his friends, they had so much fun and learned to so much. Thanks for sharing on our Afterschool Blog Hop!

  14. So cool ! My boys would love this ! We have explored a bit with marshmallows and toothpicks -
    My 7 year old is fascinated by bridges, so I know he would be completely engaged in this activity. Thanks for sharing !

  15. How fun! I love how you guys worked together to come up with a workable solution. Great job!

  16. Oh, I love the paper clip and straw idea! I tried doing toothpicks ones with my high school geometry class once but it was a nightmare to get them to stay. Of course we were doing it as a competition to see which team could make the one that could withstand the most weight. Thank you for sharing them at Sharing Saturday!! I hope you are having a wonderful week!!

  17. What a great activity and I love that you put a book with it.

  18. THANK YOU!!! So glad you see the importance of engineering with elementary kids. I do engineering projects 1-2x/week with my first graders. Ask any of them--boy, girl, "smart" or struggling learner---and they will say best part about school is engineering. They cheer when it's time! There are so many things kids learn and they don't' even realize it--- cooperation, respect, problem solving (a major life skill), how to make a plan and carry it out, how to handle failure (which is not a bad word, but something we all need to handle and learn from), listening and not just hearing, appreciation of other points of view...I could go on and on. The social skills they kids learn help create an overall feeling of safety, willingness to try without fear of being embarrassed or "wrong", and happiness in my classroom. It's so easy to take what I already have to teach and give it an engineering twist, and we all know that active learners learn more. Sorry for the long post... I taught a grad level course on Children's Engineering to in-service's my passion! Here's a great website with info and LOTS of engineering deign briefs---

    From the website

  19. At some universities this is the first group project you do as an engineer... We did this exact thing for an Intro to Mechanical Engineering class except the goal was to support a certain amount of weight.