Early classes can work, depending. We tried have a 9am Saturday kids class and a... maybe 1pm adult class, and they were both ghost towns, but the ones in the middle were fine. Then we rearranged the schedule so we had a couple of adult classes in the morning starting at 9am, and kids classes after that, and the turnout was much better. I think adults want to get up early (maybe not too early though!) and get their workout out of the way before chilling out, while kids like to sleep in or watch cartoons in the morning and then go have a fun class with their friends after lunch.