More than 2,500 students lost marks for breaking the rules in last year's GCSEs, A-levels and vocational exams, and at least 500 were penalised because their teacher was involved in the cheating.
Figures released to The TES this week reveal a 9 per cent rise in the number of penalties dished out to pupils in England in 2004, with more than 1,000 punished or warned for offences linked to mobile phones alone.
Nearly 700 youngsters were caught copying coursework, an 11 per cent increase, while more than 500 were penalised for disruptive exam hall behaviour, the figures from England's three major boards reveal.
Many Welsh students take exams set by the English boards. The number of A-level students caught cheating in Welsh Joint Education Committee papers trebled in 2004 but remained very low - at 18, against 37,000 subject entries. Most involved plagiarism and unauthorised materials being brought into exams.
At GCSE, more than half of the 80 WJEC cases (78 in 2003) involved use of mobile phones, followed by disruptive behaviour. Three pupils were punished for using personal stereos, one for impersonation, and another for assaulting a teacher. One teacher was caught cheating on an oral test.
The findings on pupil rule-breaking come with one board, OCR, reporting an eightfold increase, from seven to 55, in the number of teachers investigated for malpractice. Some 516 pupils were penalised as a result of their teacher's actions, the OCR said.
The AQA board, which handles almost half of all English exam entrants, took action against 50 teachers. OCR puts much of the rise down to some teachers providing too much help to youngsters preparing research projects for the exams.
The findings come after several annual reports on individual exams have criticised teachers - many of whom are under huge pressure to improve results - for turning a blind eye to coursework cheating.
Pupils who gain from this malpractice can lose marks even if they themselves have done nothing wrong. But Derec Stockley, WJEC's director of exams, said it came across little teacher malpractice, and teachers often exposed cheating by their pupils.
While teachers can expect to be referred to their schools for disciplinary action if they break the rules, pupils can be punished with warnings, zero marks for specific papers, andor for entire subjects. For the most serious offences, such as impersonation, candidates' results can be cancelled in all subjects and they face a five-year ban on taking any public exams in Wales and England.
Mr Stockley said: "It's very disturbing when cheating happens and the penalties are severe. But they are very small numbers when you consider the number of subject entries we have."