Meanwhile, his students are packed into classes at W.H. Maxwell Career and Technical Education High School and P.S. 13, schools in East New York, worlds away from the beach. P.S. 13 found space for about 700 Scholars' Academy students in closets, halls, offices, the cafeteria, "every single place we can imagine," P.S. 13 principal Sabrina Fleming said.

"A lot of them, they didn't have food, they didn't have clothing, they didn't have a place to stay. For a lot of them, they just wanted a place to come together," Fleming said. "That's why I said, 'You know, how can we not give them this opportunity, where they can come together and at least be with their friends?'"

It's tough on the teachers, too, Fleming said. When Scholars' Academy teachers walked in, many had lost their homes. The P.S. 13 faculty hugged them. For kids, staff members distributed outline drawings of a child and asked the kids to fill in their emotions.

"They lost everything," said Fleming, who now shares her main office with a second set of staff members. "The emotions are definitely high here. So, the first week, it was a lot of counseling for their staff ... we are definitely able to relate to their loss."

There are tests looming, ceremonies already missed. They recently held parent-teacher day in a big auditorium at a replacement school. The fall sports season is flying by, with no plan yet for how to replace the Scholars' Academy Seawolves equipment or musical instruments.

"When you go to the beach as a kid, you build a sandcastle. And as a kid, you learn early on that, sometimes, that tide comes in and it wipes out your sandcastle. What you do, when you can, you don't necessarily move your location," O'Connell said, speaking like a kid from Rockaway Beach. "You rebuild."

CNN's Poppy Harlow contributed to this report.