"[Robbie is] a prefect, an extremely gifted and talented performer and a student leader," Tony Cederwall said.
"He is actively involved with the Salvation Army youth group and works in the Charity Store.
"Robbie is known for his infectious smile, cheeky wit and caring personality. He has a magical way of brightening up your day and always makes you feel special and important to him."
Police earlier said the crash involved a Toyota Hilux, with a number of people in the vehicle and on the tray. The vehicle was reportedly doing "doughnuts" on the beach before it rolled.
The vehicle had then been righted and the driver fled.
Police arrived to find seven people still on the beach. One youth was seriously injured and six others had moderate to minor injuries.
The seriously injured youth was flown to Auckland Hospital and the others were transported to North Shore Hospital.
The driver then returned.
Waitematā East Area Commander Inspector Sundip Patel said alcohol was a factor.
"This group has made some bad decisions, which have been irresponsible and reckless, and as result seven people have been injured, one very seriously.
"I cannot emphasis enough the need to not take risks with lives when driving, and ensure others are not put in danger," he said.
"Beaches are not safe for driving on with the constantly changing environment and debris."
An 18-year-old man has been charged with dangerous driving causing injury and is due to appear in the North Shore District Court on Thursday. Further charges are likely.