But some schools are staying away from the move and others say an improved assessment system is needed because the present one is too hard.
Kelston Girls College assistant principal Jan Harvey said the school had offered performing students credits but the increasing workload had meant only smaller groups - those with about 10 students - were now offered them.
"It's an awful lot of work, it's the logistics and the time," she said. "It's so hard... they have to get people in to video [the students]. If it's so hard to do, maybe there is some way of doing it better... it's all very difficult."
Manurewa High School has offered Polyfest students credits for four years.
Dance teacher Shaquelle Maybury said that every year it was hard and despite what some might believe they were not "easy credits".
"Those who don't have the right technique or expression will get a 'not achieved'. It definitely is extra work ... I adore it [but] it's time-consuming."
Secondary Principals Association president Patrick Walsh said a set model was needed to make things easier for teachers.
"The workable solution would be for schools to get together to approach NZQA and try to devise a system which will allow greater access to the credits for performance in the Polynesian Festival and still retain the robustness of the credits they get," he said.
Students can achieve credits in Year 11, 12 and 13 in achievement and unit standards a teacher has chosen.
For example, Year 12 students can gain credits under the achievement standard Dance 2.4: Perform in a theatre dance work.
Among the schools looking into the process this year are Auckland Girls Grammar and Mangere College.
On a teachers' online forum recently, a teacher said they had more than 300 students "who live and breathe the Polyfest each year" and as a result they were looking at setting up an NZQA-approved model to assess students and therefore offer the chance to gain credits.
At Mangere College, the teacher in charge of dance, Catherine Thomson, said the school decided last year it would offer Polyfest students credits this year.
"With the sheer volume of students that we have participating, they wanted to reward [them] for the work that they put in. I was hired last year ... to implement this process."
That involves students being filmed performing in a group. They are assessed on factors including dance choreography, movement, technique and co-ordination.
Mrs Thomson said the work was excessive but teachers and tutors worked hard for the sake of pupils.
"All the teachers involved in Polyfest do it as extra from their work-load. But deciding to take on the challenge of giving students credits does increase that work-load.
"It would be nice to have a Polyfest-specific standard, but there are standards that we can use that suit Polyfest," she said.
NZQA deputy chief executive Richard Thornton said yesterday that it was delivering new assessment support material to help teachers with assessments.
Now in its 37th year, the event starts today with performances on the Diversity Stage featuring Indian, Chinese, Middle Eastern, Cambodian, African, Tuvaluan, Bhratnatiyam and Sri Lankan groups.
Performances on the Maori, Tongan, Niuean, Samoan and Cook Islands stage run tomorrow, Friday and Saturday.
