In some rural places the bus drivers take them home for Monday morning, and school probably just started, so pictures from a few weeks prior could be from the summer. I dont know if they take busses home in that district. Probably not though. This needs to be ruled out before making an educated opinion on this issue. They could just be burned up in various driveways. Edit: School security is much tighter than when I was younger, taking busses home probably doesn't happen these days.