A former Eton College teacher has been jailed for five years for a string of sexual offences against pupils during "nocturnal" visits to their bedrooms.
Matthew Mowbray, 49, went into boys' rooms under the guise of discussing school work, Reading Court Court heard.
He was found guilty of eight counts of sexual activity with a child and not guilty of one against a girl.
Judge Heather Norton QC said Mowbray had committed the "grossest breach of trust" to children and their families.
Mowbray previously admitted to six counts of making indecent images of children and one of voyeurism.
The geography teacher, of Locks Heath, Southampton, was dismissed from his role at the boys' boarding school, near Windsor, Berkshire, following his arrest.
At his trial, in which he did not give evidence, the court heard he would pay regular "nocturnal visits" to boys "for his own sexual gratification".
One complainant said Mowbray groped his bottom with a "forceful squeeze", while another pupil said he "felt really uncomfortable and just froze" when he was sexually touched by the teacher.
Addressing Mowbray, Resident Judge Heather Norton QC said: "You knew that what you were doing was wrong but you continued to take the opportunities afforded to you to abuse children for your own gratification."
She said in his position at Eton he had "ready access to teenage boys who relied upon you, looked up to you and trusted you".
"In what was the grossest breach of trust, over a period of years and in respect of a number of children, you breached their trust, the trust of the families who placed their children in your care, and the trust of the school who had appointed you," the judge added.
The judge said the nature of Mowbray's actions, which she said were at "the bottom of the scale for this type of offending", had allowed him to "get away with it for so long".
"Had you committed a more overt sexual act, it is far more likely that a child would have reported it," she said.
"As it was, they thought it was weird, odd, unusual, uncomfortable - but not such that they would risk their school career by reporting the person who had so much influence over their lives."
Simon Henderson, head teacher at Eton College, said he was "outraged" by the way Mowbray had "abused his position of trust and betrayed those in his care".
He offered his "unreserved apologies" to those affected and paid tribute to their "extraordinary courage and dignity".
Mowbray was made subject to a sexual harm prevention order for 10 years and will be on the sexual offenders register for life.