A school bus stalls directly on top of railroad tracks and will not restart. What does the AAMVA CDL Manual require the driver to do?

AAMVA CDL Manual, Section 10.3.1 'Planning for Emergencies' (Mandatory Evacuations), p. 10-6; 49 CFR Part 380, Appendix D, Unit D1.5 (Emergency Exit and Evacuation)

Trains cannot stop quickly, and a stalled bus on the tracks is in direct, immediate danger with no safe way to predict when a train might arrive. This is exactly why the manual removes any judgment call from this scenario and makes evacuation mandatory.