A school support worker who posed as a teenage girl on the web to entice boys to send him indecent images of themselves has been jailed.
Brian Syme, 32, befriended dozens of youngsters online by setting up Bebo profiles as two teenage girls.
Lady Stacey said he was guilty of a "gross breach of trust" and sentenced him to four years and eight months.
Clackmannanshire Council said that Syme, from Alloa, had been dismissed from his job in December 2009.
At a court hearing in July, the school worker was caught as part of an investigation by Central Scotland Police and admitted targeting more than 90 victims.
He also admitted possessing indecent photographs or pseudo-photographs of children, and taking or permitting such photos to be taken between 1 January 2006 and 11 December, 2009.
At the High Court in Glasgow, Lady Stacey said there would also be a four-year supervision period after the sentence.
She told Syme: "In my view, in light of all that I have heard and all that I have read, in connection with your case, children need to be protected from you.
"You should be in no doubt that what you did over a period of about four years was abusive of children and, given your position, was also a gross breach of trust."
Lady Stacey also said she would make a referral to Scottish ministers to state that Syme should not work with children in the future.
The court heard that Syme set up fake profiles in the names of "Niki D" and "BETHJ" and also had email accounts with MSN instant messenger system to enable him to chat to males and exchange images.
Syme had been placed on the sex offenders' register after he admitted the charges at the hearing in July.
Before the sentence was announced, Advocate Gavin Anderson, defending Syme, told the court: "The nature of the conduct he had with these young boys was clearly wrong."
Mr Anderson said Syme was "gratified" by the whole process of posing online as an "alter ego" as well as the conversations he had with the boys.
He also told the court Syme had contributed "significantly to society" in his work and that Syme "regretted" what he had done.