So one quarter of Californian schools were starting between 7 and 7:30? I'm surprised there haven't been revolts in the streets about that. That's completely ridiculous.
Apparently this is to accommodate parents who need to leave for work at ridiculously early hours, but if you want to accommodate parents, why only those, and not the parents who prefer to get out of bed a bit later?
My wife and I have arranged it so that she works early (she often leaves at 7:15 when the rest of the family is barely out of bed) and is home in time to pick the kids up from day care, while I take the kids to school at 8:30 and am usually home a bit too late to pick them up (though I work fairly nearby and can still pick them up if I have to).
But if this isn't an option for whatever reason, why not take your kids to pre-school care? Leave early, drop the kids off at pre-school care, go to work, and when school starts, pre-school care ensures the kids get there on time.