When we went to catholic school in socal, we started the day after Labor Day and went until the middle of June. When I got there I was half a year ahead of the other seventh graders.
it used to be that way here in California, too... i remember starting school after Labor Day... usually the next day... then when i was in high school, we began one week after Labor Day... but we always got out in June... it used to be the first week.... then it moved to the second... and so on... there is one charter school here in town where the kids get 4 weeks off in the summer... and they go to school from 8 am-4 pm--starting in Kindergarten... and believe it or not, most parents who send their kids to this school are proud that their kids are in school for all that time...