The zone that extends as much as 30 feet from the front bumper, 10 feet from the left and right sides of the bus and 10 feet behind the rear bumper of the school bus is called what?

Danger Zone.

Danger zones are areas where children are at risk of being struck by traffic during unloading and loading. Generally, these areas extend to 10 feet of either side of the bus, 10 feet behind the rear bumper, and 30 feet in front of the front bumper.

Source: Alabama CDL Manual