One teacher said that instead of the seven or eight A* grades regularly achieved by her GCSE classes, this year there were none.
But an Edexcel spokeswoman said that nationally 37.2 per cent of A-level art and design students had achieved A grades this year a 2 per cent rise on the year before.
However, Rebecca Morgan-Jones, joint head of art at Toot Hill secondary in Bingham, Nottinghamshire, said: "There is definitely something wrong."
Miss Morgan-Jones said that, for the past four years, around seven or eight of her 60 GCSE students had been awarded A*s. This year, not one achieved this gold standard.
And many of Miss Morgan-Jones' A-level candidates also achieved a grade lower than expected this year, she said.
Peter Chesney, head of art at Newark and Sherwood College in Nottinghamshire, said 90 per cent of his students achieved a grade lower than expected.
Mr Chesney, who has over 30 years' experience of teaching art A-level, said he could not understand what had happened.
Dr John Steers, general secretary of the National Society for Education in Art and Design, said he had taken up the matter with both Edexcel and the Qualifications and Curriculum Authority, following complaints from art teachers.