An 11 year-old girl was left behind on a Monterey School Bus yesterday, when the bus was parked for the school day. Bella, who has autism, was picked up for school, but not delivered to her classroom. Instead, the bus driver (who has been placed on administrative leave) failed to properly perform the mandatory sweep of the bus before parking it for the day, and the aide (who was busy with another student who needed extra assistance yesterday) failed to make sure that Bella got to class. More than 2 hours later, Bella was found curled up in the back of the bus.