Say What', Paperback

Wait, what did you say?
Sukie is worried -- her parents are acting strange. When she runs in the house, her dad asks, "If all your friends jumped off a bridge, would you jump off a bridge too?" When she eats peas with her fingers, Mom yells, "You'll put an eye out with that thing "
What is going on? She and her older brothers decide to investigate. And what they discover leads to a kids-against-parents war