Eleanor's ELECTRIFIED third-grade-bridge-project

Eleanor's bridge, inspired by Portland's St. Johns Bridge

The third graders around here spend their school year studying Portland history and as Portland has a lot of bridges, they also learn a thing-or-twelve about bridges.  Vertical lift, double-decker vertical-lift, double leaf bascule, truss-beam, cantilever truss-beam, cable suspension, and double-decker steel cantilever truss-beam are just a few of the new terms at our house (those are all bridge design styles, and we have all of them in Portland).  And at the end of the year, at the very end, right when things are getting so harried you simply can't take anything else, the third graders launch into their bridge building project. Which, by the way, is all done at home.  (?@#$!)

Eleanor's drawings of arches for her bridge.

The instructions to the parents went something like this: help your kids but don't help your kids.  Uhhh, ok.  I expected that to mean I should really just throw her in and let her sink or swim.  But the kids were told that their bridge had to be structurally sound enough to hold up a hot-wheels car.  Ok, soooo... that seemed to rule out leaving her to build it out of scrap paper.  Additionally, Eleanor had big dreams for what her finished bridge would include, so I knew I'd have to play some sort of role in this gig.

I love the whole thing (it is the centerpiece on my dinning room table now) but the COOLEST thing on this bridge is the real, working lights.  This was Eleanor's idea and she knew just how to wire-up little LEDs thanks to a series of fantastic after school electronics/robot-building classes from the super-nice folks at Interest-Ed LLC (seriously, try their classes, grades 3-5, best science-y experience we've found thus far).  Eleanor was so confident she could wire this bridge for power she even wrote the supplies list for me.

A famous view from the St. Johns Bridge recreated.

What the parents did:
I listened carefully to Eleanor's grand vision.  Then, I talked her through the discrete work packages involved (sketching and picking a scale = 1 hour; finding supplies = 2 hours; cutting parts, building up land, glueing together = 5 hours...yadda, yadda, yadda).  Then I showed her how this mapped out on our calendar, given her other commitments.  She adjusted her vision some, but still, her goal was ambitious.  And while she regretted the commitment to come home from school and work (instead of play) a few times, it was only a few times.

I worked the utility knife to cut her designs out of thick matt board. I cut the wood base, size strictly set by school. I helped brainstorm supplies, and then helped find them.  I tried to keep her spirits up... this is really the biggest job in any school project: help keep her buoyant when the doubts and difficulties start weighing her down.

Mike showed Eleanor a more complicated circuit, for flashing lights, but in the end Eleanor wanted to go with a circuit she could confidently construct herself (and thus more confidently troubleshoot, should something go wrong with the circuit once at school).

here is that famous view