Married teacher Simon Parsons, 52, secretly had sex with the 17-year-old at the Castle School in Thornbury - where he had taught for 30 years - as well as at hotels and the home he shared with his wife and two children.
The shocking affair - which was only revealed when the girl's family reported the teacher to the police years later - is the latest in a string of court cases to hit the headlines in recent weeks, involving illicit relationships between teachers and pupils.
Drama teacher Simon Parsons, 52, (left) was jailed today after having a five-year affair with a teenage pupil, who later fell pregnant with his child
Religious studies teacher Stuart Kerner (pictured right with wife Katherine), 44, was spared jail despite being convicted of having sexual relations with a pupil
Last week, religious studies teacher Stuart Kerner was spared jail, despite being convicted of two counts of sexual activity with a child after a judge controversially suggested the victim may have 'groomed him'.
The father-of-one, who was vice principal at Bexleyheath Academy in south east London, had taken the 16-year-old's virginity in a store cupboard at the school in the same week his wife miscarried.
It also emerged that his wife Katherine - an acting headteacher at a school in London - is standing by Kerner, prompting a wave of worried parents to withdraw their children from the school.
And in another case, a teaching assistant was today spared jail for having an affair with a 15-year-old pupil, in which he groped the teenager by touching her breast and sent her explicit messages.
Teaching assistant Andrew Tetley, 28, (left) was also spared jail despite being convicted of having sexual relations with a pupil
Andrew Tetley, who worked at a school in Lancashire, was handed a suspended sentence after the judge at Preston Crown Court accepted his claim that he believed the pupil was 16 - despite the fact he had access to records which would have confirmed her age.
Experts today said that the deluge of cases was a reminder of the seriousness of teachers abusing their positions and that apparent ignorance of the law was no excuse.
Sarah Green, acting director of End Violence Against Women Coalition, told MailOnline: 'These cases show how apparently ordinary teachers in ordinary schools have groomed girls and exploited their position of power.
'Offenders may try to tell themselves that what they have done was not serious but in fact the impact on those who are abused can last for many years.'
Louise Pennington, member of the Everyday Victim Blaming Campaign, added: 'Realistically, relationships with pupils is all part of the training and the law is very very clear.
'Teachers are in a position of power and, for that, the age of consent is 18 - it is not 16 and has not been since 2003. We are looking at some 12 years since the law has changed so they really should know better.
'Of course, ignorance of the law is no excuse as all teachers know exactly what the law is. They know it is a criminal offence.'
And Jon Brown, head of the NSPCC's sexual abuse programmes, said the charity was 'shocked and saddened' to hear about how the teaching staff had abused their position with vulnerable young people.
In the case of Parsons, the court heard how the teacher first had sex with the girl - who cannot be named for legal reasons - during a birthday trip to London for her 17th birthday.
The pair had met when the pupil was 13, but the relationship continued after she left the secondary school.
Parsons, of Dursley, Gloucestershire, would see the girl at weekends, take her out for meals and the theatre and to his home.
The court heard how Parsons’ wife 'bore' the affair and forgave her husband, who eventually returned to the family unit after the girl ended the relationship in her early 20s.
In an email to Judge Neil Ford QC, the Recorder of Bristol, his wife said: 'He is not a monster, he is a gentle man who made a massive mistake.' Yeah, over and over and over...
Police only arrested the respected teacher after the girl’s family uncovered the identity of her child’s father and wanted to protect other pupils.
The father-of-two later admitted five counts of sexual activity with a child in a position of trust.
Defending, David Scutt said Parsons thought 'it was something that had been wanted and pursued'.
But, in a statement read to the court, the girl, now a successful actress, said: 'I felt grossed out at one point and then I thought "Oh well, he fancies me".' Good grief!
During sentencing, Judge Ford told Parsons: 'You were a mature married man with a child of your own. She was your pupil living at home with her parents.
'You didn’t see the girl as a victim of unlawful or inappropriate behaviour but you now know that your behaviour has had a real impact upon her.
'I am sure that she is right when she describes the consequences of your actions as resulting in her feeling confused and lost.
'She said she was let down by a teacher whom she looked up to and trusted.'
He added: 'Pupils from time to time will find themselves attracted to teachers. A teacher, of course, has a duty to ensure that he does not take advantage of that situation.
'It is important that the public appreciate that those who behave as you have will receive immediate custodial sentences.'
The judge said sentencing guidelines offered him the opportunity to suspend a sentence of immediate custody.
However, he handed Parsons the highest sentence the guidelines would allow, having reduced it following the teacher’s early admission of guilt.
Parsons, who resigned as a teacher last year, was also banned from working with children and vulnerable people in the future.
Inner London Crown Court was told that Kerner (pictured) took the then 16-year-old's virginity in a store cupboard the same week his wife miscarried and later had sex with her at his family home
Last week, Kerner's case caused outrage after he was handed an 18-month suspended sentence by Judge Joanna Greenberg QC at Inner London Crown Court.
Kerner, of Ashford in Kent, had been convicted last month of two counts of sexual activity with a child by a person in a position of trust.
But he walked free from court after the judge said it was clear his 16-year-old victim was 'obsessed' with him and 'pursued' him.
Judge Joanna Greenberg QC told him: 'There is no evidence that you groomed her... It was she who groomed you and you gave in to temptation.'
The Attorney General later announced the case would be investigating following complaints of 'undue leniency'.
The National Association for People Abused in Childhood had sent the ruling sent out 'the worst kind of message to abusers – or the best, if you are one'.
Its chief executive, ex-teacher Pete Saunders, said: 'If you cross the line, if you go as far as sex as in this case, you have violated a child and deserve the consequences.
“This perverse statement by the judge puts the responsibility for abuse, as this was, on to the victim.'
In another twist in the controversial case, Mrs Kerner, acting head at Wyborne Primary School in Greenwich, has been placed on 'enforced leave' while council chiefs decide whether she should be allowed to continue working with children.
She has always publicly backed her husband, attending each day of the trial and later calling the victim a 'liar'.
Under the Childcare (Disqualification) Regulations 2009, a person can be banned from working with children aged under eight 'by association', if they live in the same household as another person who is disqualified lives or works.
Meanwhile, today in Preston, the court heard how Tetley admitted sexual activity with a child as a person in a position of trust.
Preston Crown Court was told that Tetley, who had also touched the girl's breast, believed she was 16, despite having access to records which would have confirmed her age
He was handed a six-month jail term, suspended for two years by Judge Andrew Woolman, who said the background to the case meant it was 'unnecessary' to lock him up.
The court was told the relationship came to light when the school's assistant headteacher heard rumours of a sexual relationship between the pair.
These cases show how apparently ordinary teachers in ordinary schools have groomed girls and exploited their position of power - Sarah Green, acting director of End Violence Against Women Coalition
Miss Worsley said that the girl explained her first contact with keep fit fanatic Tetley was via Instagram.
She later told police she and Tetley had initially talked about her career prospects but she became sexually attracted to him due to his good looks.
Miss Worsley said the pair exchanged telephone numbers and continued to speak and in interview the girl said that they had met up within a couple of days of making contact but knew 'it was wrong'.
The court heard that the pair had met twice over three months when they had visited a pub, with both occasions initiated by the girl, who was just weeks away from her 16th birthday.
During these meetings, they had talked and kissed, and on one occasion he had touched her breast.
Miss Worsley said: 'She said it was proper kissing, with tongues, and she was happy with what he had done.' Was it proper breast-touching too? If kissing with tongues is proper kissing, what qualifies as improper kissing; or do I really want to know?
During a police interview, the girl said the pair had exchanged a series of explicit messages involving their sexual fantasies and where they could have sex.
'He asked for photos of her and there were very sexual conversations,' Miss Worsley added.
Today, the mother and father of Parsons's victim said the fact he could no longer work with children brought them 'some closure'.
'Every parent sends their child to school where they expect them to be safe and to find out that school is the very place where your daughter is abused is a very horrifying ordeal for your daughter, and indeed all of your family, to have gone through,' her mother said.
Her father added: 'It is obviously a significant sentence and gave a strong message.'