Most students in the Atlanta Public Schools head back to class next week. On Wednesday, APS Superintendent Meria Carstarphen said the district is ready. That's a different tune than the one she sang three years ago. Like us on Facebook At that time, Carstarphen was new to APS. She said she was surprised by the district's lack of basic systems. There were no structures in place for planning student schedules, master schedules or establishing bus routes, she said. This year, she has a different worry. "I'm nervous because I can't find a major problem,” Carstarphen said. “We've got transportation routes done. Master schedules are done. Parents can find their stuff. Kids can find their stuff." Carstarphen says it took time — and a lot of work — to get to this point. "We feel ready, and it's the week before, not the day before,” she said. “And for APS, that's a huge step forward. Most of the time, we've been running to the wall." A bigger challenge hit the school district last month when