Earlier quoted context omitted.
If school starts at 7:30, then that kid isn't waking up fresh at 7, they have to be woken up significantly earlier. I shudder to think of the other examples in the comments which have to already be in school at 7.
If kids get to bed around 8pm they will normally be up at around 6-6.30 plenty of time for most to get ready. But sure if they are put to bed at 9-10 then its going to be tougher.
The moment I got into university and could move my schedule my GPA went up two grades.