Nathaniel Okusanya, received a life sentence with a minimum term of 20 years.
Nelson Idiabeta, detained at her majesty's pleasure, received a minimum term 19 years
Passing sentence his honour Judge Marks QC told the two teenagers:
"You have shown not one iota of remorse, both of you seeking to brazen it out in front of a jury."
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Highs on Thursday of 18C.
Barnet Council ran the school, which was an institution for young people with learning difficulties.
Bowers pleaded not guilty of assaulting his ex-fiancee Sophia Cahill in Croydon in January.