Cherryll Pepper, 52, is taking a local education authority to court after being dismissed by governors of Montem County First school in Slough, Berkshire. She had been accused of attempting to mislead them into giving her a larger pay increase than she was entitled to but was exonerated by a Reading employment tribunal which described her sacking as a "blatant case of unfair dismissal".
She was awarded pound;15,000 by the tribunal, as compensation against the school's actions, but now says the local education authority must compensate her for failing to properly advise governors in their handling of the disciplinary procedure.
Reading council inherited liability from the now defunct Berkshire County Council, which was the LEA at the time of her dismissal, in 1996. Berkshire amitted liability. But Staines County Court last week decided the amount of damages should be decided by the High Court, at a date to be fixed, because the likely amount exceeded its powers.
The National Association of Head Teachers, representing Mrs Pepper, wants a six-figure sum.
Mrs Pepper has suffered ill-health since her dismissal although the family does not want to discuss this in detail until the High Court hearing in London.
She is working full-time as a teacher at Clifton primary school in Southall, west London, and lives in Windsor with her husband Ray, who said: "It has obviously taken its toll. We have had an awful lot of support from the NAHT and David Hart, the general secretary, has been directly involved in my wife's case.
"She was well on her way to becoming a headteacher when this happened and I don't think that will happen now."