ARS 28-701.02 makes it a crime approach a school crossing driving above 35 mph. The law also prohibits going more than 20 mph above any speed limit. If a speed limit is not posted, a person is not allowed to travel more than 45 mph in a business or residential area, or more than 85 mph in other areas.
In the state of Arizona, if you are found to be driving at excessive speeds, you will most likely be charged with a class 3 misdemeanor. A class 3 misdemeanor is of middling severity within the misdemeanor system, but still certainly should not be disregarded.
If charged with a class 3 misdemeanor, a defendant may face up to 30 days in jail, and/or incur fines of up to $500. Repeated offenses may incur more severe consequences, dependent on the specifics of your case.