A major announcement on funding for schools is expected from the Prime Minister this morning.

Jacinda Ardern is set to speak at Auckland's Onehunga High School just after 9am.

Head of the Education Institute at Massey University Professor John O'Neill says some school sites are in serious disrepair.

He says there are three key areas which need to be addressed.

"One would be areas where there's huge population growth, two would be areas where there is significant population decline over time, and then there is maintenance as a whole."

LISTEN TO JOHN O'NEILL TALK WITH MIKE HOSKING ABOVE