(a) Whenever authorized signs are erected indicating any street or part thereof as a play street, no person shall drive a vehicle upon any such street or portion thereof except drivers of vehicles having business or whose residences are within such closed area, provided that such drivers shall exercise the greatest care in driving upon any such street or portion thereof and provided further that all traffic approaching intersections at such play streets shall stop at all barricades at such intersections and cross such play streets with caution.
(b) Whoever violates any provision of this section is guilty of a minor misdemeanor on a first offense; on a second offense within one year after the first offense, the person is guilty of a misdemeanor of the fourth degree; on each subsequent offense within one year after the first offense, the person is guilty of a misdemeanor of the third degree.