Regarding school start times, In our district, the students begin to enter the building at 9:15, although a lot of kids are in the school, grounds much earlier than that just hanging out.
Due to bus schedules, an earlier start time is not possible. I do like the suggestion of the end of the school day being used for make up work and clubs and activities.The current times of 9:15 and 3:35 dismissal really conflict with the schedules of the working parents.
The students are much better in the morning but have reached capacity by the end of the day. Many districts are looking into extending the school day in length to help with the problems of latch key kids and juvenile crime and violence.
Good luck with your quest, Chris B.