District of Columbia Code Division VI. Education, Libraries, and Cultural Institutions. § 38-3107. School zones.

(a)(1) School zones shall have a speed limit of 15 miles per hour between the hours of 6:00 a.m. and 7:00 p.m.; except, that on arterials, DDOT may increase the speed limit in school zones to 25 miles per hour at all times except the hours designated for student drop-off and pick-up for the school day and regular afterschool programming.

(2) DDOT shall post signage on all roadways within a school zone that states the speed limit and warns that the area is a school zone.