The Liberal Party has set a target of lifting Tasmania's performance on NAPLAN testing to the national average in six years.

The number of Tasmanian students that achieved the minimum standard was below the national average in each of the 20 areas tested.

Under a Liberal government, the first 10 specialist literacy and numeracy teachers would begin work in term 3 of the school year, with the rest in place by the end of its four-year term.

"This is an emergency for many young people," Mr Ferguson said.

The extra staff would work in clusters and teach at a number of schools, but it's unclear how much time each student in need would spend with a specialist.

Mr Ferguson said that would be determined on a case-by-case basis.

"Quite clearly the greatest need ... is in our high school years. It's quite appalling to think that the longer you spend in the Tasmanian education system, the further you fall behind."

AEU Tasmanian president Terry Polglase praised the $8.4 million policy, but said its success would depend on how the teachers were deployed across the state's 60 public high schools.

"The role they play and the degree to which they are able to embed themselves within the staff and to have the time to connect and talk with class teachers will be crucial to its success," Mr Polglase said.

Labor Education Minister Brian Wightman said the focus on NAPLAN testing was too narrow.

"NAPLAN is one of many assessments and measures that tell us how our education system and our students are performing," Mr Wightman said.

"The focus must always be on the literacy and numeracy of our children, on providing the best possible education, not on ticking a box on a scorecard."

Greens leader Nick McKim, who was Education Minister up until last month, said the focus had to be on improving education in the early years.