A woman teacher is facing a jail term for having sex with an under-age boy at the special needs school where she was a maths teacher.
St Albans Crown Court heard Susan Hogan, 46, from Great Innings North, Watton at Stone, Herts, began having sex with the pupil when he was 14.
On Monday she pleaded guilty to three offences of abusing a position of trust by having sex with an underage boy.
She is due to be sentenced on 21 March. The maximum jail term is five years.
Hogan pleaded not guilty to indecent assault on a second boy and indecency with a third youngster.
Miss Isabel Delamere, prosecuting, said the Crown would not be seeking a trial in respect of those two charges.
Judge Findlay Baker QC adjourned the case so that a pre-sentence report can be put together.
Hogan, a mother of four, taught at the school for special needs youngsters which specialised in teaching children with behavioural and emotional difficulties.
Hogan is said to have had sex with the youngster between September 2002 and April of last year.
Claire Robinson, defending, said Hogan was no longer teaching and worked as a book keeper at an old people's home.
Judge Baker granted her bail, but made it a condition that she must not teach any persons under the age of 16.
Following her conviction, her name will also go on the sex offenders' register.