Yes, in Georgia curfew for juveniles (those under 17 years old) is a state law. O.C.G.A. 15-11-2 (12) (E) states an Unruly Child is any child who Wanders or loiters about the streets of any city, or...
Although anyone 17 or older doesn't have a curfew, under 17 is 10:30 pm- 6:00am Monday-Thursday, and 11:30pm-6:00am Friday & Saturday. Here is the link to Cook County Curfew...
Written laws can mean any number of things. They could be constitutions of a country or state. They could mean the Code or Statutes or Ordinances of a specific government.