The man, now 62, was convicted of having sex with the former student, who was 46 years younger than him, over a six-month period in 2010, AFP reported.
The court also ordered him to pay the girl’s mother 3,000 euros in damages.
The prosecution had sought a three-year prison term, partially suspended.
The victim’s mother, who is no longer on speaking terms with her daughter as a result of the scandal, was “evidently extremely disappointed” with the sentence, her lawyer, Simon Bergeras, is quoted as saying by AFP.
She felt it was “unfortunately not a penalty of the kind to send a strong signal to teachers who might be tempted to cross the red line”, Bergeras said.
The mother, a civil party in the case, filed a complaint against the former teacher for “sexual assault of a minor under the age of 15”.
The incidents occurred between July and December 2010 when the former teacher was giving a one-on-one course to the adolescent.
The lawyer for the teacher said the mild sentence “was a becalming decision that allowed everyone to turn the page,” AFP reported.
His client, who lives near Grenoble, “recognised, assumed and regretted the facts”, he said.
The case follows a six-month jail sentence handed to a 39-year-old woman earlier this month by a court in La Roche-sur-Yon (Vendée) for having sexual relations with a 12-year-old boy.
The teacher, who taught at a traditional Catholic school, testified that she had experienced a “love story” with the child.
In addition to the prison term, the court banned her from praticising any activity that brought her into contact with minors.