A GALASHIELS janitor who slipped on Vaseline is suing the council for £50,000.
Linda Gillie banged her head and suffered bruising to the leg after the prank at the Academy in 2009.
The end of year sixth-form joke left the 53-year-old with a 12cm scar. And her lawyers are claiming not enough was done to stamp out the pranks.
Legal papers lodged at the Court of Session in Edinburgh claim that an English teacher had previously been sprayed with sardines hidden in a hand-drier. And that boot polish had been left on seats.
According to the documents Mrs Gillie, who was working as an assistant janitor, was asked by a teacher on May 12 to clean up Vaseline which had been smeared on banisters near the school's science department.
The papers also claim that condoms had been left on door handles by the school leavers. Her lawyers state: "At the said school the sixth year pupils habitually performed pranks in their last week of school.
"In the years preceding the said accident, leaving sixth year pupils have thrown eggs and tomato ketchup at the school, placed sardines in lockers, left dirty nappies in the school, left fish in the library, put washing up liquid down the toilets and black boot polish on seats."
It is claimed that Mrs Gillie slipped on Vaseline which had been left on steps, causing her to fall down the stairs.
She later had to have procedures under general anaesthetic to remove a fluid swelling in her left leg - and she was unable to return to her previous job until October 2010.
The papers allege: "The council took no steps to discourage sixth year pupils from performing such pranks in the last week of school."
Scottish Borders Council is fighting the case. The local authority's lawyers claim the £50,000 sought is excessive and say the nature and extent of the janitor's injuries is not known and not admitted.
A spokesman for the council added: "I can confirm that this claim has been litigated. It would be inappropriate for us to comment any further."