Parents of 100 16-year-olds at an Essex school were yesterday told in a letter of the mistake, which involves 500 scripts and four different exam boards. The teacher responsible for sending off the papers, Jill Hearsey, who was the school's examinations officer, has been suspended.
Around 600,000 teenagers across the country will discover their GCSE grades tomorrow. But some pupils at the 922-pupil James Hornsby High School in Basildon will find that results for as many as five subjects are missing. The main subjects affected are English, maths, science, design and technology.
Jackie White, the school's head, did not realise until last week that the papers were missing after a call from one of the exam boards asking why they had not received the scripts.
She said: "I said this could not be possible and questioned the teacher concerned. She admitted she had not sent them off. She was well aware this was so but she could not give me a rational explanation." She added: "It is inexcusable but I was repeatedly reassured by my examinations officer that the scripts had been despatched."
After a search, Mrs White discovered the papers. A spokesman for Essex county council said: "The head was not told until last week. The first inquiries from the exam boards went to the examinations officer who had not sent them off.
"Our immediate priority has been to look after the students because they are not going to get a complete set of results.
"The exam boards have been superb. They have agreed to accept the scripts and to mark them. The students should get the results in about a fortnight's time." The letter to parents from the head says: "I write to inform you that there will be a delay in the publication of some of our examination results.
"This is as a consequence of our examination officer's failure to carry out her duties competently. The member of staff concerned has been suspended pending a full investigation."
A meeting will be held on Thursday evening to update worried parents.
The school has been in touch with colleges where pupils are hoping to go and believes that their places will not be jeopardised by the results having been delayed.