From their website:
Millennium Brooklyn will hold two informational Open Houses for prospective families. They will take place on Wednesday, October 25th, 2017 from 6:30 to 8:00 PM and Saturday, November 4th, 2017 from 10:00 to 11:30 AM. Informal tours will take place immediately following each Open House. No registration is required for Open Houses, but please be aware that both events are well attended and space is limited!
At last year’s high school fair I spoke to people from the school and they said they still are taking kids who aren’t from Brooklyn.