If you haven't heard of it before, d3o is this material that acts soft and pliable when at rest, but instantly locks up when impacted and returns to its original shape right after. They're using it in beanies, ski jackets, soccer goalie gloves, etc.
They don't give out samples to students, but I do have a hat with it built in that I can bring to the next class.
This is the material I originally attempted to work with for this class. It is a concrete-impregnated layered fabric with a waterproof backing that is flexible and bendable but fully hardens 2 hours after becoming wet.