Strike action will hit Northern Territory schools today, but the Education Department says most will remain open.

The NT branch of the Australian Education Union had planned for its members to go on strike on Thursday this week, but has moved it to Friday after threats from the Government.

Teachers were warned that the planned two-hour stoppage on Thursday would result in them being docked a full day’s pay, so the strike was moved in response.

“If we are going to be docked a day, we will take a day,” the union's NT president Matthew Cranitch said.

The industrial action comes as the result of ongoing demands to address teacher shortages and growing class sizes in the Territory.

The Education Department says 24 remote schools will close tomorrow, but a majority of sites in higher-populated areas will stay open.

The Australian Education Union expects 70 per cent of its 2,500 members will join the strike.

Education Department spokesperson Suzanne Bowden said all schools in Darwin, Palmerston and Nhulunbuy will be taking students today.

“In some cases ... it will be business as usual because there may only be a couple of teachers out, while in other schools the normal school program may be disrupted,” she said.

“However, there will be enough school staff there to provide adequate supervision.”