They deal with careless motorists and unruly children.
Most school bus drivers are on the job just a few hours each day. But those morning and afternoon routes can be quite demanding.
The biggest challenge is keeping an eye on the road and the kids.
Harrison County school bus driver Diane House is responsible for the safety of some three dozen children. Staying safe means watching the road for careless drivers, while also keeping the kids in line.
"Young man, keep your hands to yourself," House yelled to a boy at the back of the bus.
A big yellow bus should attract attention on the road. But you'd be surprised at how many drivers fail to stop when the bus does.
"People just don't pay attention. They just don't pay attention to the sign. They think they don't have to or either they're just glazing off somewhere else and not looking," explained the veteran school bus driver.
Dropping off the kids is easy enough. Keeping them in line, on the bus, is something else.
Dealing with the noise is one ongoing challenge with a bus load of kids. Drivers must also dole out discipline.
"All of them started telling me, Miss House there's a fight, Miss House there's a fight! I can't stop in the middle of Highway 49. I have to wait until I can get to a place where I can pull off, separate them and then take them to the office the next morning," she said.
Along with keeping tabs on the kids, bus drivers must keep a constant watch on the road. They wish others would be just as careful.
"And when you see that big, yellow sign that says school bus stop ahead, there's a school bus stop ahead. And if it's school picking up or dropping off time, you're probably going to meet one there," House said.
Bus drivers also want parents to be aware of behavior aboard the bus. House says some are quick to complain.
"Johnny hit James and you didn't do nothing about it. And I said, well, I have to glance at the road every now and then."
Take a ride on the school bus and you'll better appreciate what can often be a thankless job.