Classes are back in session for Illinois schools, which means motorists need to remember to follow a few rules of the road they've been able to ignore over the summer. Especially because those rules can carry some stiff penalties.

During the school year, drivers are sharing the road with on-duty school buses. But some of the biggest safety concerns happen when one of the vehicles isn't even in motion. Kids run the greatest risk of being injured while they're at the bus stop, according to the Illinois State Board of Education. In fact, most children between 5 to 7 are hurt or killed boarding and exiting the bus when they're in the area around the bus that the board of education charmingly calls the "Death Zone." Here's what you need to know—and what you should do—when you see a bus stopped with its flashing lights and extended stop-sign arm:

Passing a Stopped School Bus The Law: In Illinois, all lanes of traffic in both directions must stop when a school bus is stopped to pick up or drop off kids while traveling along a two-lane road. This also applies to one-way streets no matter how many lanes of traffic. On a four-lane road with at least two lanes of traveling moving in the opposite direction, only motorists in going the same direction as the bus are required to stop.

RELATED: Speeding in a School Zone in Illinois: Laws, Fines Drivers also should stop at least 20 feet from the bus when they see the bus' flashing lights and stop-sign arm extended in order to let students cross the road safely.

School bus drivers also can report the license plate numbers of vehicles that illegally pass them to police. Under state law, the vehicle's owner must tell authorities who was driving at the time of the infraction or face the charges themselves, according to the Illinois State Police. The Penalty: First-time offenders can look forward to having their driver's license suspended for three months, and recidivists who are convicted a second time within five years could have their license suspended for a year. Offenders also can face fines of $150 for the first conviction and $500 for subsequent offenses.