The Secondary Principals' Association says the methods used by schools which are more successful at keeping Maori students in education, need to be examined.
New Ministry of Education figures show a 12 year low, in the rate at which schools are suspending, standing down, excluding and expelling students.
But Secondary Principals' Association president Patrick Walsh says there is still a disturbing number of Maori students in this group.
Mr Walsh says some schools are proving to be better than others at keeping Maori boys, in particular, in education, and more research on their practices is needed.
The figures show schools temporarily stood down 13,700 students last year, and suspended nearly 3500.
That means they're suspending just over five children in every 1000, compared to nearly eight children 12 years ago.
Continual disobedience, assaults on other students, drug use, and verbal abuse of staff were the main reasons schools punished students last year.