In most cases, all drivers are required to stop when meeting or overtaking a stopped school bus that has its red lights flashing and its stop arm extended when loading or unloading passengers. The only exception to this rule is when highways are separated in the center by a dirt, grass or concrete median. In this situation, only vehicles following or traveling alongside a school bus in the same direction must stop. A warning that a bus stop is about to take place will always be given with the flashing amber lights on the front and rear of the school bus. Upon seeing these flashing amber lights, vehicles approaching the school bus from both the front and rear should immediately slow down and prepare to stop. All drivers must pay special attention to children, be focused and exercise caution when in the vicinity of a school bus stop, as student riders can sometimes be unpredictable. Once the bus is fully stopped, the flashing red lights will activate and the stop arm will deploy. Vehicles must stop and should remain stopped until all loading students are aboard in the morning or all unloading passengers have cleared 12 feet off the roadway in the afternoon. Motorists should proceed with caution, only after passengers have cleared the roadway, the stop arm is cancelled and the flashing red lights are deactivated.