DALE - which stands for dynamic alternative learning environment - caters to students from years 3 to 12 with a range of social and emotional difficulties including anxiety, depression, post-traumatic stress disorder and autism.

The program was founded at St Philip's Waratah in 1997, and was introduced at the Cessnock campus in 2012.

It had 30 students when it moved into its own building at the southern end of the Nulkaba property in 2016, and now has 60 students from all around the Hunter region - and a waitlist.

The school's population will remain small, to benefit students who find the size and noise of large schools overwhelming.

"It is for students who have the capacity to achieve in a mainstream curriculum, but are unable to do so in a mainstream environment," DALE principal Bronwyn Thoroughgood said.

Ms Thoroughgood said DALE Cessnock has been modified to meet the needs of students, with the outdoor learning areas an important addition with its "space, openness, peace and natural landscape".

"Research has shown the positive impact outdoor areas can have on mental health," she said.

Liberal Senator for NSW, Arthur Sinodinos was at the school on Friday to celebrate its latest milestone, the official opening of its new indoor and outdoor learning areas.

The school received $650,000 for the projects through the Federal Government's Capital Grants Program, which provides funding for non-government schools to improve capital infrastructure.

Senator Sinodinos said students would benefit from the new learning areas that would be regularly used by students, as well as by parents and the community for assemblies and school concerts.

"It was great to visit St Philip's Christian College DALE to see the new facilities and hear about the positive impact it will have on students," Senator Sinodinos said.

"St Philip's Christian College DALE has a wonderful school community, and these new learning areas will further enhance the learning environment."

Senator Sinodinos, the newly-appointed Ambassador to the United States, said school funding has increased every year under the Coalition Government.

"We are ensuring that every child gets a quality education no matter where they go to school," he said.

"The Coalition Government is providing record funding for government, Catholic and independent schools.

"We are delivering real, needs-based funding that is matched by national reforms that will drive better results and outcomes, as recommended by David Gonski in his Review to Achieve Educational Excellence in Australian Schools.

"Our Government is funding improved facilities at schools, like the new learning areas at St Philip's Christian College DALE, as part of our commitment to education."