When 5-year-old Tre-Vaughn Dysart saw his classmate slip underwater his instincts kicked in.
He rushed forward, lifted the boy above the water and took him to the side of the pool where a teacher helped them both out.
Police yesterday praised the young hero for his quick-thinking actions which they say potentially saved the other boy from drowning.
The incident unfolded in the school pool at Hamilton West School in December. Teachers were poolside during the fun swimming lesson when the inexperienced youngster got into difficulty treading water in the middle of the pool.
Teachers Tammy Williams and Debbie Leet said the younger boy had just started school and had no water safety experience.
"Tre-Vaughn was amazing. He just grabbed him," Mrs Leet said.
Ms Williams: "That's quite amazing for that age because most children don't take any notice of their surrounds."
Before a teacher could dive in Tre-Vaughn quickly lifted the boy's head above water and pulled him close to keep him upright.
"He just hugged him and brought him back to the side," Mrs Leet said. "The little boy hugged back."
Tre-Vaughn helped the boy to the side of the pool where a teacher was waiting.
"The lovely thing is we teach water safety but often at that age they don't take it in," Ms Williams said. "So it's good to see that teaching works and he had paid attention and knew what to do."
Mother Jojo Ahu said she was "immensely proud" of her son who loved water and had spent time at the beach.
Ms Ahu said the shy Year 2 pupil seemed oblivious to the significance of his actions. However, police were so impressed they yesterday awarded the now 6-year-old a certificate marking the event.
Hamilton Police area prevention manager Inspector Marcus Lynam praised Tre-Vaughn as "one brave little boy".
"If you weren't there who knows what would have happened. You should be very proud of what you've done."
Mr Lynam said Tre-Vaughn's bravery was more than just being fearless in the face of danger.
"It's about doing what's right. And there's no doubt that what you did back in December Tre-Vaughn fits that description of being brave and courageous."
The keen basketballer was presented with the certificate on behalf of Hamilton Bluelight - a youth organisation run under the auspices of police - by three members of the Waikato Pistons team.
He was also given a remote controlled skateboard toy and a miniature police car.