Phoenix School, in Clayton, Orton Goldhay, has been expanded over two sites to create an additional 54 places for children with severe learning disabilities.
The work has created a new block to house the school’s sixth form, creating more space within the original building for new pupils.
The development was formally opened by Peterborough City Council leader John Holdich, and mayor John Peach.
Cllr Holdich said: “It was a real honour to officially open the new building, which looks excellent.
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“The extension is an important move for the city. We are absolutely committed to making sure there are enough school places for every child. In this financial year alone we are spending £26 million to create more than 1,800 places. We want to ensure we provide city children the best chance in life to succeed.
“The Phoenix School provides exceptional teaching and support for its students. This new building will mean that the school can reach out to more young people with disabilities in the years to come.”
n recent years, the city council has created more than 180 additional special school places at the City of Peterborough Academy Special School, Phoenix School, Heltwate School, Marshfields School and NeneGate School.