Liam Ross, 30, from Dartford, appeared at Woolwich Crown Court on Monday (March 2) where he was jailed for 12 years.
He had pleaded guilty to ten sex offences including the rape of a 12-year-old girl.
His offending took place in the borough of Bexley.
Ross said he believed the girl was old enough to consent, but rape of a child under 13 is a strict liability offence meaning the defendant’s belief about the child’s age or her consent does not factor in.
Judge Ruth Downing said she accepted Ross’ claim that he believed the girl was older, stating that she thought the same when she saw the victim.
Ross was also found guilty by a jury of the rape and sexual assault of another schoolgirl who was 16.
Judge Downing described it as a “difficult and rather disturbing” case, as Ross had pursued “lawful but inappropriate” relationships with schoolgirls who were over the age of consent.
He had received a letter from the police warning that his relationship with one 16-year-old girl put him at risk of criminal behaviour, but he continued undeterred.
Whilst the sexual relationship with the 16-year-old girl had been consensual at one point, Judge Downing said, Ross later raped and sexually assaulted her.
Ross had been a coach driver who frequently drove schoolchildren – though his offending was said to have no connection to his work.
A pre-sentence report described elements of predatory and reckless behaviour in Ross’ personality, though Judge Downing said she disagreed with much of the report.
Judge Downing said she was confident that Ross would realise the “utter folly” of pursuing sexual relationships with 16-year-old girls.
She said: “This might send a message to those who think sailing close to the wind, being risky, is something they might like to do.”
Ross will remain on the sex offenders’ register for life.
Alongside rape of a child under 13, the offences Ross pleaded guilty to included paying for the sexual services of a child, causing or inciting child exploitation, sexual assault of a child, and multiple indecent image offences.
