South Cambridgeshire MP Heidi Allen braved the cold to open a new mobile classroom at Thriplow Cof E Primary School.
The school had hoped to secure money from developers to build more classrooms at the school, but a recent planning application for new houses in the village was turned down so they have bought a mobile classroom instead.
The MP was shown round the school by headteacher Victoria Penty and former governor and volunteer David Easthope.
She then cut a celebratory cake with school ambassadors Fintan and Isabel.
Headteacher Victoria Penty said: “We were delighted to welcome Heidi Allen to our school. She showed a great interest in the school and its development and assured us she would continue her campaign for more funding – both for Thriplow Primary School and for other schools across Cambridgeshire.”