After consultation with several schools and bus companies, RollCall has developed Bus Guardian which is a system that helps to ensure that no child has been left on the bus. It does this by enforcing the bus driver (or other supervisors) to walk to the back of the bus and tap onto a RollCall control board positioned there.
All this information can be tracked centrally on a dashboard and reports to ensure that all drivers have checked their bus before leaving. This makes it virtually impossible for a bus driver to finish their run without walking the bus and checking for students.