Cub Scout Presentation
Cub Scout Presentation
(OP)
I'm presenting engineering to the 4th graders in my son's cub scouts tonight. I had planned on discussing a little bit about what a structural engineer does. I'm also going to bring in a transit and do some surveying. I would like to have them do some kind of project also. When I was in 7th grade, we had an assignment of supporting as much weight as we could using a single sheet of paper. I think it had to be at least 4" high and maybe some other rules. We only have 45 minutes though, so I'm looking for something similar but less time consuming. Also I need to keep in mind that they are 4th graders.
Does anyone have any engineering experiment in mind?
Thanks,
Drew
Does anyone have any engineering experiment in mind?
Thanks,
Drew






RE: Cub Scout Presentation
BUILD A TOWER
Materials: One pound of spaghetti (uncooked), 10 oz. bag of miniature marshmallows, box of paper clips or other light weight item, ruler or tape measure, paper for drawing designs
Procedure: Set the stage: students are architects and engineers who must use the materials at hand, spaghetti and marshmallows, to design and build a tall tower that can support the weight of a box of paper clips.
Other idea can be found at http://www.centexeweek.org/Experiments/Elementary_Exper...
RE: Cub Scout Presentation
Thanks Rich
RE: Cub Scout Presentation
RE: Cub Scout Presentation
RE: Cub Scout Presentation
In a bowl, place some sand to the top or almost, and place a relatively dense "building" shaped object, steel bar or rectangular rock...
Then slowly add water to the sand thereby simulating liquefaction, and watch the resulting instability occur, (think PISA).
Easy, and cool.
tg
RE: Cub Scout Presentation
Explain to them where this goes in a building, what it does, and point out that you never see buildings that fall down, they alway fall over.
Those little models are amazingle rigid (especially the paper "shearwall" one). I used this method here at work to help some of my architectural coworkers
RE: Cub Scout Presentation
Thanks. Were you able to get the architects to understand? Did they spec out 20lb bond paper instead of 1/2" gyp on the next project?
RE: Cub Scout Presentation
They understand, but they don't want to. All they get out of it is that we don't need to bother with all the bracing and shear wall nonsense and just use moment frames for everything
RE: Cub Scout Presentation
An easy way to demonstrate the effectiveness of a truss is to fan fold a sheet of paper, then glue the vertices to two other sheets. Use plain notebook paper and school glue from your son - the boys will have real life experience with them. Then glue three sheets of paper together like a sandwich, with the glue in a similar pattern to the "truss" section - and the same amount of glue as well. Let everything dry thoroughly.
You can then use these two props to demonstrate the effectiveness of trusses. In turn, use them to span between two supports - and apply increasing loads until they fail. The truss section will be much stronger - and since you used the same amount of glue on both, the shape has to be the cause of the increased capacity.
You could use this as a hands-on activity; let them compete to see whose bridge is strongest -
Have fun!
Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora.
RE: Cub Scout Presentation
I was thinking about Guassian elimination for the resolution of a stiffness matrix or the principles of finite elements, but these may be more appropriate!
RE: Cub Scout Presentation
RE: Cub Scout Presentation
tg
RE: Cub Scout Presentation
I did some presentations for Engineer's Week a few years back. We built a popsicle stick bridge in the office and brought it into the classroom. We asked the kids to guess how much it would hold before it collapsed. Being ultra-nerds, we actually ran an anlysis on RISA, or some such program, and had a CAD drawing.
Two lessons emerged: middle school kids like to break stuff, and popsicle stick bridges are tough little monkeys--it held about 300 lbs.
RE: Cub Scout Presentation
I then had a transit and showed them how to use it. By the time we took two measurements my time was up.
I did like the ideas you guys gave and I think I might do some of them next year if they ask me again.
RE: Cub Scout Presentation
If I do it again for my youngset son I will bring in a lap top and show them some structural as well as civil/topographic models on screen. Maybe by the time he is in third or fourth grade the idea will be blaize.
I really enjoyed all the other ideas in this thread!