K'nex: Bridges

"K'nex education:  Bridges- structures and design-
We'll be examining :
* Design Process & Compression
* Tension & Load (Dead and Live)
* Force Stress & Cantilever Construction
* Suspension Technology & Keystone
* Abutments and Anchorages
* And more

The class will contain one part architecture and one part building and examining
concepts. The class is made for busy bodies. On the last class
day, the kids will build a bridge and test it's load capacity."

So begins our adventure of doing this project as a class.  We've finished week 2, and we're off to a great start. I'm actually using both bridges K'nex education sets and teacher books.  The intro to bridges and the K'nex real bridges series, as both have something great to offer.
The intro to bridges is a great introduction, but for homeschoolers, we want more "why" to our books than the intro offers.  It is superior in teacher accessibility and has great worksheets (yes, I know some you hate that word, but there is a place for it sometimes :) that help the kids understand the differences in bridges and visualize the vocabulary that I than have them put into practice.  The Real Bridges set however, has far more, "look this up on the internet and write a paper about it." than I care to use.  That has value, to be sure, but in a class setting filled with 8 kids and 4000 (no I'm not kidding) K'nex doing research is the last thing on my list of possible things to occupy our time.  The Real bridges does a much better job of telling the story of the science behind bridges and has some fabulous bridge online sites that it offers at the end of each lesson.  It includes some nice upper math skills (Young's Modulus) that we aren't doing as a class, but that I'm making available to the parents whose children are interested and desire some deeper facts about the specifics of the math behind structural integrity.
        The intro set is perfect for a "class" of 1 or 2 and is ideal for 2nd-4th grade.  The Real Bridges set says it can take on a "class" of 24-30 students appropriate for (a strong academic 4th, regular) 5th-8th grade student, but there's no way that one set is helping out 24 kids without some of them being seriously bored watching the other kids do all the work.   I have twice the number of k'nex as that one set, and I am doing fine with 8 kids in 4 teams of 2. We occasionally come close to running out of corner pieces (if you have a set, you know the ones- they're usually purple and make right angles. Extremely useful. )  It also took me a just a little while to figure out how they had written the manual to that set.  They separated it into three parts.  Because my expectation was that the kids would be working with the k'nex pieces in each lesson - I mean really, why wouldn't you?- my confusion came from trying to figure out where the lesson- aka building- was.  It was in part three, and spattered in the teacher's notes.  They suggest building ideas in the teacher's notes that I actually didn't think were always apart of the "readers" they gave the kids.  You don't build their awesome "real" bridges until the very end.  Those plans are shown in the intro to bridges book, and are so cool and impressive to make.  
  I like my plan better :) We build every day we're together for k'nex.  I've combined the lessons in real bridges with the building projects and building ID worksheets in the intro kit to create an active, engaging class that hopefully peeks at the why and where of bridges for a spectrum of learners in 2nd-5th grade.
---I should mention that we make about 3 bridges per team and allow each team to keep each bridge up until the end of class when we take a photo and then dismantle the bridges for the next class.   We hold classes at the Williamsburg Classical Academy.