The state government is facing a $20 million repair bill for recovery work at 178 schools in bushfire-affected areas as it prepares to re-open all schools for the first day of term in late January.

The federal government has also stepped in with $8 million for mental health support and $400 in additional recovery payments for each affected student, Federal Education Minister Dan Tehan announced on Friday.

Gail Austin, an asset services officer at School Infrastructure NSW, has been working on the local public school's recovery in bushfire-ravaged Cobargo. Credit:Kiran Ridley

Bobin Public School on the Mid North Coast and Wytaliba Public School in the Glen Innes region were destroyed in early November when fires tore through the state's north. Other schools have suffered damage ranging from lost fences and burnt play equipment to contamination from ash and fire retardant.

Speaking from Bobin Public School on Friday, which is being reconstructed, NSW Education Minister Sarah Mitchell said communities in northern and southern NSW had "experienced an absolutely harrowing bushfire season" which impacted many local schools, but she expected all to be open for the first day of term in 12 days' time.