It was Aug. 12, the first day of the 2014-15 school year. The second-largest district in the country started using a new integrated student information system dubbed MiSiS to serve more than 640,000 students in more than 900 schools, and it wasn't working right. In some cases, students were left stranded without a class schedule. The data the system did have wasn't always accurate. Soon, the system slowed to a crawl. Then, the software bugs multiplied.