Dunno why this was published in Business Week, but it's a really important bit of information about sleep and sleep deprivation in kids. http://www.businessweek.com/news/2010-01-01/teen-suicidal-thoughts-may-be-caused-by-late-nights-study-says.html
The sleep issue is one of the main reasons we've kept at homeschooling (to great advantage in other areas). I personally believe that my child's health is MORE important than public schooling, and I know that for my family especially, but for most families to some degree, the early start hours for school are detrimental to kid's health, both physical and mental, because starting early causes three problems: 1) too little sleep; 2) no time for healthy breakfasts; and 3) starting the day with stress, which sets the tone for the day, dumps your magnesium supply, and inhibits clear thinking. I, personally, believe that the morning schedule is one of the main reasons kids grow up hating school--too often they arrive tired, hungry (or sugared up on cold cereal or other fast breakfasts), and stressed and are then condemned (and publicly humiliated) for not being at the top of their game.
I'm sure some families have it all together and get up early enough to do things leisurely and right and still get to school by 7:00 or 8:00 am. But I doubt it's a majority.