I can appreciate the experience. Pretty neat when they jump in willing to help. Sometimes even a little direction along the way can spoil the event for them. Actually I thought it was you under the truck. Ours are all on their own, one in heaven and one in Idaho working at INL, and now we get to spoil the grandchildren.
Letting them experience things like this and do the work has always been one of the best ways of learning. I try and be there for any truly catastophic problems...but it is good not to step in too soon.
Half of learning (and for me its been more than half by far I am afraid) is learning from the mistake of doing it wrong and then regrouping and figuring out how to do it right. Those lessons are rarely forgotten.