Education Secretary Michael Gove donned a hard hat on Monday to dig the first piece of earth for the Edgware Jewish Primary School building.
Mr Gove also reaffirmed his and the government's support for Jewish education, saying: "This government is committed to ensuring that every Jewish child who would like a Jewish education receives one. We will do everything that we can to help Jewish faith schools grow."
He was speaking as bulldozers and earth-moving machines started work on the Hale Lane site, which was formerly shared with the Edgware Adath Yisroel Synagogue. Pupils have moved to a nearby property during construction, which is expected to take a year. The new school will cost £4.5 million and maintained status has already been applied for. Building work is being funded entirely by donations from the community.
Governors' chair Eddy Breuer-Weil said: "How fitting it is that the masonry and stones that formed the walls of our synagogue - stones and bricks steeped in thousands of hours of Jewish prayers, study, joy and celebrations over the decades - will quite literally form the very foundations for the school that we are building."
Facilities will include a dedicated art and technology area, a library, indoor and outdoor play areas and a hall for drama activities. There will also be "break-out" rooms for personalised learning for gifted pupils or those requiring additional support.
Mr Gove observed that "the schools doing the best are those with the strongest ethos. Among those doing superbly are Hasmonean and JFS, who represent the very best in state education and in the Jewish community. We have so much to be proud of."
He said afterwards: "The whole thing about education is that it's a partnership. It's wonderful when a community steps up to the plate to give time and energy to making a school a success. There are different communities with different strengths but the Jewish community leads the way and that is why we are so happy to work with them." He was presented with a Chanukiah.
Other guests included local MPs Matthew Offord and Mike Freer, Ilford North MP Lee Scott, Barnet councillors and Jewish community leaders.