Board at Kings Island?
It is what you make of it.
Have you ever went to Water Works with your friends?
Throw in Skee Ball, a couple of shows, french fries with vinegar, a couple of 3 point shots, people watching while sitting under the Eiffel Tower, a cold beer at the Festhaus, a quick walk through the shops on International Street, a ride up the Eiffel Tower..... There, that should take up an extra hour at the very least. Show them what else the park has to offer.