The Education Ministry says it underspent millions of dollars of its special education budget in each of the last two financial years.
The underspending totalled nearly $18 million in the 20-12 /20-13 financial year and $14.5 million in the 20-13/20-14 financial years.
The Ministry said that was about three percent of the annual budget for special education.
It said the slow introduction of a behaviour scheme and a parenting programme contributed to the under-spend, as did a lack of uptake of increased funding for children with the highest needs.
The Ministry said some schools and the ministry also had trouble finding the right staff to work with children with disabilities.