Bummer!
Mojave Sidecar,
I bought my Jumping Jack trailer around the same time as you bought yours (Nov. 2010). Fortunately, I've been able to use mine several times since I bought it, and I hope to use it a lot more in the future.
When I insured it, the insurance company didn't know how to classify it (utility trailer or camping trailer). They ended up classifying it as a utility trailer, which is a little cheaper to insure (~$50/yr. vs. ~$70/yr.). I did get full coverage for the trailer for just the type of situation that happened to yours, or to protect my investment if someone ran into it on the highway.
I hope the kid's insurance company comes through for you, since he was wholly responsible for the damages to your trailer. I agree with the others that you should get a new trailer out of the deal, possibly minus the tent, if yours is still in undamaged condition.