Eight Otago pupils were among 330 nationwide found to have broken the rules during school examinations last year.
The Otago total was two higher than in 2007.
However, none of the breaches was considered serious enough to affect the pupils' exam results.
Figures released by the New Zealand Qualifications Authority (NZQA) yesterday showed the Otago incidents included two exam candidates from Otago Boys High School who breached the rules during more than one exam, and two from St Hildas Collegiate believed to have shared answers.
Only one breach was discovered in Southland - a girl from James Hargest College in Invercargill caught using notes in a music exam.
Her exam result was also unaffected.
Pupils sat a total of 511,000 NCEA and scholarship exams last year.
The number of breaches reported overall was two more than in 2007.
Only 62 breaches led to results being withheld, down from 116 in 2007.
The most common breach of rules reported last year involved pupils taking notes into examination rooms, with 68 incidents investigated, the NZQA figures showed.
Exam results were withheld in 28 cases.
Cellphone-related breaches dropped from 47 in 2007 to 44 last year.
Two cellphone breaches led to results being withheld.
Other reasons for results being withheld included creating a disturbance (7), inappropriate language or drawings on exam papers (6), copying (4), using another pupil's exam admission slip (1) and possessing an MP3 or CD player (1).
Exam supervisors were encouraged to report all potential breaches, no matter how minor, NZQA deputy chief executive, qualifications, Bali Haque, said.
Consequences for breaches could range from a warning letter to having results withheld.
"Breaches of examination rules are treated very seriously by NZQA but the number of breaches is a very small proportion of the total candidate numbers," Mr Haque said.
