I don't think that is a factor tbh. Back when schools start times were set 2 factors were mainly considered:

1. Being light enough out for it to be safe for kids to wait outside for the bus or walk to school. That time is earlier here in MA than in most parts of the country. Older kids could reasonably be expected to be safer with less light so they started school first. This is also a big reason why many parents and school employee oppose permanent daylight savings time, it would mean much darker mornings in the winter.
2. Sun rising earlier also means it sets earlier. In order to ensure safe travel after school and accommodate after-school actives, school had to end relatively early. Kids walking home in the dark is dangerous. And many schools don't have lights for all of their sports fields so practice and games have to be before sunset.