There’s no way you could defeat more than a dozen 7-year olds. By swinging the toaster around by its cord, you’re going to pretty quickly lose your weapon after hurting, but not killing, maybe 1-2 kids. Then they’ll quickly overpower you by sheer numbers. To kill one, you’ll have to use both hands and maybe your feet to either strangle or immobilize and continuously bludgeon them, but their numbers make them the most likely to be able to do any containing. I speak as a father of a 4 and 2 year old who can do surprising amounts of damage for average sized kids.