Police have launched a homicide investigation and Tararua College's principal said armed police were in the area.
Detective Senior Sergeant David Thompson said officers discovered the woman at the Arthur St property about 4.40pm on Wednesday.
"A scene guard is in place at the property and nearby residents can expect to see an ongoing police presence in the coming days as we conduct a scene examination and make enquiries in the area."
Police had been working with the school to provide reassurance and an alternative route for students to come and go from the campus, he said.
"We know the police presence will be unsettling but we can confirm there is no threat to the wider community."
Tararua College principal Iain Anderson said the police were at a house near the college campus.
"There's an ongoing police investigation there ... it's all cordoned off."
He said while close to the school, police weren't on school grounds.
Anderson said the students were "all good" and there were fewer at school on Thursday, due to secondary teachers' partial strikes.
School leaders would guide students safely on to the grounds, and the bus drop off point would be be changed.
Police have found a car that was taken from the victim's address but they are still looking for the driver.
The car was found in Rotorua and police want to speak to anyone who saw the late model red Mitsubishi ASX VRX station wagon, registration QGU9, travelling in the central North Island, between Pahiatua and Rotorua.
