I'm not as bugged by Sims, even kids, being out at community lots during school and business hours, simply because we haven't lived in a 9-5, M-F world in decades, and in many places, schools stagger attendance year-round, so at any point, a third to a quarter (depending how they do it) of the student body, is out of school on vacation, regardless of whether it's summer.
Also, homeschooling and unschooling have grown by leaps and bounds, and as a person with personal experience in that, I've done my share of inner eye-rolls at the "but why aren't you in school right now?" presumptions, but then, a lot of people find non-vampires roaming Forgotten Hollow annoying, so I think it ought to be under your control, whether kids and teens are out during "school hours" if that bothers you.
Your world, your way, would be the ideal way to play. :)