Each school principal or designee shall provide instruction at least twice each year for all transported students in safe practices to board and depart from the school bus including emergency evacuations. Initial instruction shall be given during the first twenty (20) days of the school year and the second period of instruction shall be given during the first two (2) weeks of the second semester. The principal and his / her instructional staff members shall determine the most effective and practical manner in which to provide such instruction.