Kids might shoot back, so I wouldn't go into the BB gun situation totally unprepared, if you know what I mean. That some serious shit, shooting at anyone with anything in this day and age. Still, under cover, the BB sniper would be hilarious.
How exactly does one piss off a jellyfish? Seriously, I'm curious, because they don't have any sort of central nervous system, and are incapable of emotional states.
As for the kids in the pool, I like the BB gun idea.