In a letter sent to parents on Sunday afternoon, Scotch College principal Tom Batty said it was impossible to imagine the suffering caused by "those who betrayed the position of trust".

"In addition to compensation the school has offered a sincere apology to the old boys concerned," Mr Batty said. It is not known how much money has been received by the victims.

The Age revealed on Monday that Scotch College had acknowledged, for the first time, that at least five students had been abused at the Hawthorn private school.

The bulk of the claims of sexual abuse date back to the 1960s. The Presbyterian day and boarding school for boys said all the incidents occurred more than two decades ago and had been resolved.

Mr Batty said the school's culture had transformed over recent decades and he told parents that the school was not dealing with any current abuse cases.

The school had consulted experts to put in place principles to ensure abuse does not occur again, he said.

"The school is absolutely committed to making Scotch a safe school in which each boy can flourish."

Last week the Old Scotch Collegians' Association wrote to thousands of former students to offer support to those who may have been sexually abused. Abuse victims were asked to seek help, if they required it, from the school's psychologist.

The Royal Commission into Institutional Responses to Child Sexual Abuse, now sitting in Ballarat, has prompted many schools to look at how they may have previously dealt with cases of sexual abuse, and has also motivated previously unknown victims to come forward.

In recent months a handful of elite Melbourne schools have been rocked by abuse allegations.

Xavier College has revealed nine cases of sexual abuse from the 1960s and '70s, but former students have alleged the figure to be "just the tip of the iceberg".

A teacher at Ivanhoe Grammar was stood down in March after being charged with 33 sexual offences that allegedly took place at the school more than two decades ago.

And claims a former teacher abused students at the non-denominational co-ed Preshil school in Kew have been referred to the Royal Commission, which has spoken to former students about alleged incidents that occurred up to the 1990s.

Carolyn Worth, spokeswoman for the Victorian Centre Against Sexual Assault, said Scotch College had responded in a positive way to this crisis.

"It's good to see that they are not saying we don't think this happened or there is some confusion about this. One of the most important things for victims is being believed."

It was important for victims to see that action had been taken, she said. "It may encourage [more] to come forward."