Shortly before 8:40 a.m., on Monday, April 18, 2005, a 52-passenger school bus was traveling westbound on Columbia Pike (State Route 244) in Arlington County, Virginia, transporting 15 elementary school children, grades pre-K through 5, to the nearby Hoffman-Boston Elementary School. On approaching the signaled intersection with Courthouse Road, the school bus driver began moving the bus into the left turn lane (from which it would turn south onto Courthouse Road) and slowed it nearly to a stop. As the driver turned the vehicle, its left front encroached slightly into the left lane of the eastbound side of Columbia Pike. The driver later stated that distractions inside the bus might have affected her driving at this time. She said her attention was drawn to a student standing on a seat and to a clipboard that fell to the floor at her driving station.