Yes, keep them off, so they can pretend to be knackered for ooh, about an hour after school starts then drive you mad all day.
Don't be daft. 1am is fine, let them sleep as late as possible, make sure everything is ready so it takes them 5 minutes to get out of bed, shove on some clothes, grab some breakfast and straight to school.
If you want them to stay off, then just talk to the teacher, sometimes teachers will be fine with it, the teacher is the one who knows how important that lesson is.
I've had Dd off school or in late (she is only just 8 though) for all manner of things, and always had the teacher's support in it. I have only kept her off for what is necessary though, so in this case, I'd take her in at first break if she was really that tired, not keep her off the whole day.