Now, parents are angry and demanding to know how it happened.
Nicole Suriel was a 6th grade student at Columbia Secondary School in Harlem. Three chaperones escorted Suriel and 23 fellow students to the beach Tuesday.
At the school, some blamed administrators for Nicole's death.
"He (The principal) sent a teacher, a lone teacher, out there with two interns. He is responsible, the principal," one parent said.
Witnesses saw Nicole near a jetty before she disappeared.
"I saw her head moving and I said why is there a little kid in the water by herself?" one witness said.
A teacher tried to save the girk and instead had to be rescued herself. She sobbed as rescuers searched for Nicole for more than an hour before finding her body.
School chancellor Joel Klein held a moment of silence for Suriel Tuesday night and asked everyone to keep her family in their thoughts.
The beaches at Long Beach opened for the Memorial Day weekend, but have only been staffed with lifeguards during the weekends.
Lifeguards will be on duty every day for the rest of the summer starting Saturday.