My 4 year old goes at 7:30, wakes up about 7:30 or I wake her at 7:45.
6 yr/old reads from 7:30 til near 8:00, has to be woken in the morning and dragged out of bed (so not a morning person).
Non school nights they stay up til after 8, maybe 8:30ish depends on how we're doing for time.