Kyle Vassil, a year 7 student at Aquinas College in Ringwood, drowned in a 3.7-metre deep waterhole at the Alpine Ash Mountain Retreat last Wednesday evening.

The 12 year old was swimming with another boy during free time when he got into trouble and disappeared about 5.30pm.

Sergeant John Elks, of Kinglake police, said teachers were frantically searching for Kyle in the murky water when police arrived. His body was pulled out by search and rescue divers about 7.30pm.

Principal Tony O'Byrne said Kyle's death had come as a profound shock to the tight-knit school community.

He said Kyle's sister, Kacylyn, and mother, Pacita, indicated Kyle was a strong swimmer and there was no indication he suffered from asthma.

"The sense that he had died in such a tragic way was of even greater shock to them [because he was a strong swimmer]. The school will offer the family all the support they need."

Students and teachers were also offered counselling.

The orientation camp was the second in a series of three to be held by the school this month. The third camp, scheduled for this week, was cancelled.

"It would be inappropriate for our next class to go to the venue right now," Mr O'Byrne said. "It just wouldn't feel right."

He said it was heartening that Kacylyn, a year 12 student at the college, had asked the school to hold a memorial for her brother. Kacylyn also asked to speak at the memorial, expected to be held next week.

Before going to Aquinas College, Kyle attended Our Lady of Lourdes Primary School in Bayswater.

Terry Foley, who was Kyle's grade 6 teacher last year, said the pupil had been very popular among his peers and "liked to be in everything".

"He was a happy child. He enjoyed the company of his friends."

Mr Foley said Kyle enjoyed all sports, including basketball, and also took part in the Rock Eisteddfod with the school.

"We were deeply saddened by the news and our sympathies go out to his family and close friends."

Alpine Ash Mountain Retreat owner Stephen Weatherhead said the camp, too, was "deeply saddened by this tragedy".

"We are working closely with the school to support and manage the welfare of all concerned.

"Our primary concern is for the student's family and the other students, staff and their families.

"We are working with all involved to understand the circumstances of this tragic accident."

Mr O'Byrne said the circumstances surrounding Kyle's death would be the subject of a police investigation and a coronial inquiry.