2 Part question about riding with your kid.

I used to love going riding pillion with my dad. I want to take my son. Can someone recommend a child's jacket for a 10 - 12 year old boy.

Is this a good idea? I am a safe driver, but man would it suck if I had an accident with my son on board. I know the risks, but what is the consensus here? Just looking for gear mostly. I think i am resigned to risking his life and hopefully getting him home safe.