Just days before they break up for the summer, teachers at 640 schools across the county are having to stay behind and work out their pupils' SATS scores, while others are still waiting for results to filter through.

Some schools, which have had papers returned, say the marking is not up to standard but they have been told they will have to pay to get them re-marked.

One school received just one paper while another was sent six boxes of unmarked scripts from another school. The catalogue of bungles unfolded today as headteachers across the county logged on to a special website for their scores.

Nearly all the county's primary and secondary schools have had papers returned unmarked, while more than 20 have contacted their union complaining about the quality of the marking.

Tony Roberts, of Penwortham, county spokesman for the National Association of Headteachers, has been inundated with complaints from schools caught up in the mayhem which, they say, has been caused by outsourcing marking to American-owned ETS Europe.

Last week, as the Lancashire Evening Post reported, marking for the Key Stage Two and Three papers was behind schedule but the Government promised they would be ready before the end of term.

Mr Roberts said: "What is happening now is getting almost surreal. We are getting towards the end of term with a growing number of schools who still have nothing.

"I heard stories from local schools who have had papers back which have been marked but the results not added up so staff had go through them all and tally them, leaving no time for appeals."

A Bamber Bridge primary school revealed none of its English SATS papers have been marked.

Steph Smith, headteacher of St Mary's and St Benedict's Roman Catholic Primary School on Brownedge Lane, Bamber Bridge, said: "I'm trying to access the SATS site at the moment. The English papers have come back unmarked – it has been just a fiasco."

Mr Roberts added that some schools had received some, but not all papers, and many are worried about the quality of marking.

Their fears were compounded by tales from local teachers who were being offered extra money to mark papers.

Mr Roberts said: "One marker received scripts very late and was given £100 bonus for marking them within the deadline."

Another was approached to go away for five days and was offered £180 a day plus £2.50 a script plus hotel bills and the cost of supply cover at her school was offered.

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