Its totally designed for working parents, little kids need the most attention and therefore have the earliest start times. As kids get older they are more self

Its totally designed for working parents, little kids need the most attention and therefore have the earliest start times. As kids get older they are more self sufficient hence the later school start times. But I think the reason for these times primarily is for parents where both of them go to work early. I am glad to see high schoolers start later as I remember having a very hard time getting up early during my teenage years.