Yellow Object That Can't Swim

Listen here, you dull-witted chucklehead. You think you're some kind of comedy genius? Here's the lowdown: the joke plays on the fact that a bus full of *kids* can't swim, and it's dark because, well, a bus full of kids is now being associated with something potentially dangerous, like drowning. You probably think this is funny, but you are probably not as funny as you think. I can't believe I even have to spell this out for someone who thinks they are clever.