The "DREADED" Toothpick Bridge

[dg39]

I heard so many horror stories about toothpick bridges, that I always hoped my dd would never get this assignment. My two older kids (in their 20's) never had to do it, so I figured maybe we would get lucky and this one wouldn't have to do it either.

Well, I was wrong. They've been discussing it in class and doing research on various bridges. Any day now, she'll be bringing home all the necessary information about constructing it. I will help her (no, not do it for her, just help her) and was wondering if any ones children had to do it, if you have any pointers for us.

 

[ckay87]

Never heard of this, but I'll be paying attention to this thread. I'm a Cub Scout leader with a group of Webelos working on their Engineering pins. Bridges are a topic we need to cover. Sounds like a cool project (?) No (?)

 

[Lisa loves Pooh]

I made mine with popsicle sticks (we had much more leeway in materials for our class that the prof did later limit for future classes).

I did a criss cross design and it held 250 pounds.

My question for you is what weight are they supposed to support and are there any other restraints on dimension?

Mine was done for Physics--but I just thought simple geometry and remembered something about triangles being a better support system than squares....

So I did 3 or 4 layers of sticks glued together....they were angled at 90 degrees roughly (maybe less, I didn't measure) and on one layer they went in one direction and on the next layer it was the opposite direction and then alternated for the number of layers. It didn't look like a functional bridge or anything--just something that could have weight supported from it.

I would encourage her to research different designs of bridges, what types of different structures their are and which she think she might be able to best replicated.

The bridge--and the dropping an egg 3 stories without a parachute were my 2 most favorite science projects ever.

 

[Lisa loves Pooh]

I would not show these to your daughter per se unless she happens upon them herself..but here are some samples of toothpick bridges:

http://www.pisymphony.com/toothpick/toothpick1.htm

http://homepage2.nifty.com/SUBAL/BCTOPE.htm

http://www.uen.org/utahlink/activities/view_activity.cgi?activity_id=7498

http://www.yesmag.bc.ca/projects/bridge.html


The technique of glueing multiple tooth picks together to make stronger building materials is the concept I used with the popsicle sticks. Though my bridge didn't look anything like these bridges!

Since "answers" on how to do this are contained with the links, you may limit her research to a library or to just bridge design and not allowing her to research toothpick bridges.

 

[Sandy V.]

Whatever you do, make sure that the teacher sends home the rubric on how the bridge should be built, required materials, things that are "no-no"s. I would INSIST on one if the bridge is going to be worth more than a minimal grade.

DS did this in middle school and the extremely DISORGANIZED teacher told them "just go build a bridge out of toothpicks and glue" and that was it. DS built a great bridge all by himself (DH hovered, though ). Well, he ended up getting downgraded because he used the "wrong" type of glue according to her. With no rubric handed out, we fought that one with both teacher and principal. Thankfully, we won that battle!! I can't stand it when the kids are given an important project, but no parameters on which to follow to actually DO it.

P.S. DD did the egg drop structure. If your kid ever has to do that one, we had great success by mixing Elmer's glue and toothpicks in an old blender (to be thrown away, obviously). Pulverizes the crap out of them and you create a great material to use for building a protective shell.

 

[kaw1218]

I heard so many horror stories about toothpick bridges, that I always hoped my dd would never get this assignment. My two older kids (in their 20's) never had to do it, so I figured maybe we would get lucky and this one wouldn't have to do it either.

Well, I was wrong. They've been discussing it in class and doing research on various bridges. Any day now, she'll be bringing home all the necessary information about constructing it. I will help her (no, not do it for her, just help her) and was wondering if any ones children had to do it, if you have any pointers for us.

I'm just curious, how old is your DD? I wonder if this would be a good project for my DD10 and her cousin who's 12. they are always looking for a new project.

 

[hiwaygal]

For those of you looking for "engineering" related projects, I know of a couple.


First, there is the National Future City Competition (www.futurecity.org). It is for 7th and 8th grade students. They use SIM City to design a city of the future, they write an essay/abstract, and they build a 3D model of a portion of their city. Then they bring the whole thing to a regional competition and present it to a panel of judges. A very cool program!! I organize it for my area, and I'm ALWAYS looking for new schools!!!

Also, our local chapter of the National Society of Professional Engineers sponsors a "bridge" competition. Unfortunately, I don't know much about it, but you can contact any local chapter of several engineering societies to see what they can do to help you find projects for your schools!!

Some others to try:

American Society of Civil Engineers (ASCE)

American Soceity of Mechanical Engineers (ASME)

Institute of Electrical and Electronics Engineers (IEEE)

 

[Lisa loves Pooh]

P.S. DD did the egg drop structure. If your kid ever has to do that one, we had great success by mixing Elmer's glue and toothpicks in an old blender (to be thrown away, obviously). Pulverizes the crap out of them and you create a great material to use for building a protective shell.

I did suspended panty hose in a shoe box--basically tied that sucker so that the egg was in the middle of the box.

 

[dg39]

Thanks for all the replies.I couldn't find the thread & would have replied sooner. Well, my dd (12yrs.) got all the needed info from her teacher (2 pages full of requirements). This is turning into a high school project if you ask me, but....Anyway, we have all the toothpicks and glue and are just waiting to start. My dd's gung ho about this,and thinks (hopes)her bridge will hold 2 bricks w/o falling apart. I'm going to look at the websites posted and get some ideas, but, my dd already "informed" me,that its "her" project and both me & my dh can't help. That's all I needed to hear. She's on her own with this. I'll just clean up the mess, LOL...Thanks again...

 

[SC Minnie]

DD has to do that last year in 6th grade. Use lots of wood glue. Hers had to be sturdy enough to hold 2 text books. It wasn't the prettiest thing in the world but it did the job and got her an A.

We had to do the egg drop/toss thing too.