This information is from the DOE's website.
Elementary or middle school: Register at your zoned school starting on Wednesday, Sept. 9 (the first day of school). Call 311 or try the search at the DOE website to determine your zoned school. If you don't have one, visit a Student Registration Center in your borough of residence beginning Monday August, 31.
High School: Register at a Student Registration Center in your borough of residence beginning Monday, August 31.
The Centers will be open Monday - Friday 8am - 3pm from August 31 to Sept. 18. Closed Sept. 7 for Labor Day. Translated materials and interpretation services will be available at all Centers. Check out the DOE's new student page for documents that you will be required to bring.
Brooklyn High School for the Arts
345 Dean St. between 3rd and 4th Ave.
Clara Barton High School
901 Classon Ave. east side of the Brooklyn Museum between Union and President
4200 16th Ave. at 42nd St. Brooklyn
Brooklyn Technical High School
29 Fort Greene Place (enter on South Elliott) between Dekalb and Fulton
PS 46 just called with a registration update for their school.
They are holding early registration Sept. 1-4, 9am to 1pm. The parent or guardian should come to school with the child's Birth Certificate, immunization records, proofs of address and their ID.
They will also be holding an evening meeting for parents of enrolled students to meet teachers on the evening of Sept. 10.