Jamie jumped, but he told Paul he did it because Fenn and Summer were bullying him. I assume that's true - I FF through pretty much every scene with the kiddies, unless there's a grown-up in the same scene. Paul went and gave Phyllis, Michael, and Lauren hell for their rotten offspring.
I have never liked Lauren, but I am at her going all cougar with Carmine. This show has sorely needed a nasty affair since...I dunno, since Nikki and Vicki had a go with Deacon Sharpe (oh, I miss him ).