Love Tap has a reputation for being excellent at taking care of children. Twilight needs somepony to help look after the sirens. These two things really shouldn't have any connection, but desperate times call for desperate measures.
Apple Bloom, Sweetie Belle, Scootaloo, Button Mash, Dinky, Rumble, and Silver Spoon are sent to a summer camp for two months, where they are split apart into the two competing camp teams.