The Educational Institute hopes the days of pushing teachers to the brink are numbered.
A new report has revealed teachers and principals are working long hours - and children's education is suffering at the same time.
President Lynda Stuart says teachers are burning out under the pressure, and substitute staff are not a permanent solution.
"Our education system has relied on the goodwill of teachers and principals for many many years now, and that needs to change," she says.
"Our relievers are wonderful people, but they don't have necessarily the in-depth knowledge around that particular child in that particular leaning environment, and what works best for them."
The shows two-fifths of principals are highly stressed, and 75 percent want more time to focus on educational leadership.
Ms Stuart says a funding boost would do everyone a favour.
"Having the additional funding to have people in schools to support teachers around behavioural issues and learning support issues would also be something that would help."
The report also found eight percent of executives think funding is adequate, however 92 percent of principals believe their operational funding is inadequate.