This week I had a rare opportunity to co-teach in a summer enrichment program for elementary students. Our topic was "engineering--bridge building" and anyone who knows me will likely think that's pretty funny since math and measurements are not my strong suit. However, since the lead teacher is a math and science whiz, it was great fun following her lead and working with such enthusiastic kids.
We started the week learning the lingo -- types of engineers, types of forces, types of bridges. We tested shapes and and played with forces -- tension and compression--and talked about how those affect bridges.
Next we learned about live and dead loads. We used paper to test how much live load could hold before collapsing. First the kids tried a single sheet across the top of two books. Next they placed a sheet of paper in the form of an arch below that paper to add support and finally they accordion folded a sheet of paper and placed that between their arch paper and the flat sheet.
One little boy was soooo excited by how it worked he was determined to jot it down so "he wouldn't forget" and he wanted to keep track of how many paper fasteners he was able to put on the paper before it collapsed--170. (note how he wasn't quite sure how to write the numeral. :) )
On the second day we tested shapes for the piers using rolled up paper and did some computer activities. The kids ranged in age from 1st grade to 6th grade and so that age range was a bit of a challenge. Then we paired up and created pasta bridges using an activity that demanded the kids plan, create a budget (since they had limited "dollars/points" with which to "buy" their supplies) and use their time wisely since they only had an hour.
On Wednesday they tested their pasta bridges and the kids were amazed at how much weight they held and we all learned from WHERE they broke. The look on the kids' faces as their pasta bridges snapped in half was priceless! Finally we were ready to start on our popsicle bridges. We were building a truss bridge in pairs that we were planning to test out on Friday at the university on our field trip to the engineering dept.
The popsicle bridges were more frustrating because the glue was slow to dry and kids were impatient and less than precise and this demanded more precision. We did spend a fair amount of time talking about reinforcing our bridges where they were weak. On Thursday we had a speaker from UND who showed the kids a few more bridges and talked about trusses and how bridges are actually constructed. He also introduced them to the computer program--West Point Bridge Design where they could design bridges and test them. They loved that!
Friday's popsicle bridge breaking was a little anticlimactic, but the entire field trip was well received. The kids broke their bridges and then we actually saw how concrete is created and just how strong it is... We put a small concrete cylinder in a machine and broke it using 200,000 pounds of pressure. When that thing shattered, it sounded like a gun shot!
The next phase took us to a geological engineer's classroom where he talked about the soil and the ground and plate tectonics and how important it is for the engineers to plan for things like earthquakes and the like. He did an extended Google Earth tour and I was quite impressed with how much the kids knew about different countries and volcanoes and tall mountains.
Our presenter was a rock star with the kids. He really knew how to work the crowd and had them entertained from the start. We ended our day by making structures with spaghetti and gum drops and trying to make the tallest self-supporting structures.
Mr. Y was terrific when it came to dealing with the kiddos whose towers had fallen and were only a few centimeters high because they'd come apart. They'd try to show him how high it WAS before it broke and he'd insist on measuring it in its current state and we recorded heights on the board. Then he'd assure them that they had a lot of room for improvement and they should try to figure out where things went wrong because everyone got to try it again! He just turned those frowny faces into ones full of purpose and then after both trials were done we did some basic math to determine whose was highest, what the average height was, and who had the most improvement.
In all, I was really quite impressed with the way the kids responded to some pretty big ideas and how eager and excited they were to get in there and try things. Yay for learning.
Some websites we used in planning this week: