I see nothing wrong with school starting this early. By starting in early to mid August, it allows the school to have several scheduled days off such as winter break, spring break, and days for parent-teacher conferences. The bonus is that we still finish the school year before June.
If school started later, one of two things would happen. There would either be less days off of school during the school year, or school wouldn't get out until June.
Now, let me toss out another option. Honestly, I think it would be really cool to go to a school that has classes year round. Some schools have implemented the system of year-round school, and they only have school Tuesday through Friday with a three day weekend every weekend. I myself would really enjoy this system, especially if it was combined with frequent breaks.
Maybe it is just me, but I work a lot better when I have a longer period of time to do work and am able to have frequent breaks. A schedule like that would apply really well to school. Students would have a longer time to complete homework and more time each week to "turn off" and recharge.
Having school year round is a controversial opinion, but it is one I stick by, And who knows? Maybe if I went through a year of that schedule I would hate it. All I can do now is speculate.
For the time being, I think school starting earlier in August is a good plan, and should at the very least stay that way, or start even earlier than we currently are.