The infraction or offense of speeding in a school zone is committed when the driver of a motor vehicle in a marked school zone exceeds the posted speed limit or exceeds the speed limit that is reasonable and prudent under the circumstances or conditions—conditions such as the road (straight, curved, wet, dry, icy, flat, hilly); the weather (clear, foggy, raining, snowing); the visibility; and the presence of children in a crosswalk, for example.

Laws regarding speeding in a school zone vary from state to state and among cities and towns and are usually located in a state’s statutes and sometimes in local ordinances enacted by cities or towns.

The penalty for speeding in a school zone is usually a fine and demerit points added to the driver’s license or driving record. But the fines and penalties for speeding in a school zone are usually much greater than for a typical speeding ticket or citation.

In Montana (MT), speeding in a school zone is considered a serious traffic offense due to the heightened risk to children and pedestrians. The state's traffic laws dictate that drivers must adhere to the posted speed limits, which are typically reduced in school zones during certain times of the day when children are likely to be present. The exact speed limit can vary, but it is often set at 15 to 25 miles per hour during school hours. Fines for speeding in a school zone in Montana are generally higher than for other speeding offenses, and the penalties can include increased fines and points on the driver's license. Additionally, the fines can be doubled in some circumstances, reflecting the severity of the offense. It's important for drivers to be aware of and comply with the specific speed limits and traffic regulations in school zones to ensure the safety of children and to avoid the steep penalties associated with violations.