Tho with VoD dominating all entertainment, what are kids doing nowadays when waking up early at a Saturday?
In any case, everybody has different circumstances. Parenting is an improvisational pursuit, every kid has different needs. In my kid's case, end-of-semester sleep deprivation has more than typical impact because of hypothyroidism that requires carefully adjusted medication and really benefits from a regular sleep schedule. Engineering school? Regular sleep schedule? Pffft. So I cut some slack. Their tendency to over-sleep alarms is partly wonky body chemistry.
I recall oversleeping for a final. Luckily, it was an intro programming, you-mean-I-can't-test-out-of-this?? class. I walked in a hour late, and left a 1/2 hour early. Had that been DiffEQ or similar.... errrf.