Low literacy rates don't just impact New Zealand's schoolchildren.

The flow-on effect bleeds into adulthood, affecting their university and ultimately career prospects.

"If you want to go to university, clearly you have to be able to read and write at a high level," Dubby Henry, a New Zealand Herald education reporter, tells the Front Page podcast.

"And we want everyone to be able to do that so all different sectors of society can be represented in fields like medicine and law."

But this issue goes beyond students interested in university-level study.

"If you want to be a plumber or a mechanic, you still need to be literate and numerate," says Henry.

If people don't have these fundamental skills by the time they leave school, then the path to entering the productive economy becomes that much more difficult.

A research report published by The Education Hub earlier this year revealed that by the age of 15, 35.4 per cent of teenagers struggle to read and write.

Since the late 2000s, the performance of New Zealand students in international standardised tests measuring numeracy, literacy and science performance has steadily declined.

These trends are worrying, given that literacy rates can be a strong predictor of the economic and career prospects of young people leaving school.

At the extreme end of this, you see this reflected in the prison population across New Zealand.

"The Department of Corrections believes that about three out of five prisoners don't have [an] NCEA Level 1 level of literacy or numeracy," explains Henry.

"So, they're not going to have qualifications when they leave prison. And they're not going to be able to get a job, which is also a really important predictor of whether you're going to stay out of prison."

This all shows the gravity of ensuring that we take steps now to limit the long-term impact of declining literacy rates across society.

Listen to the full podcast to hear what's being done, or read Henry's investigation into our literacy rates beginning here.