St. Ann Gichocho Girls, Kiambu,is a private boarding school, sponsored by the Archdiocese of Nairobi,providing the Kenyan Curriculum for secondary education. It has a very unique History, dating back to 2005. It was started to realize the dream and vision of the Congregation of the Sisters of St.Ann, to provide a platform on which every girl child can develop excellence in academic performance and character in school and beyond; with integrity to the glory of God. The dream got a place for reality at Gichocho, as a result of the observation of Mr. Ndungu Mbugua, the then chairman of Gichocho sub parish.

The school began to function in the 3 vacant classrooms of Gicoco primary school, adjacent to the present where students from the locality were being admitted. The first principal was Sr. Sunita and the school had only 3 members of staff, Sr. Silvy Jose, Mr. Peter Gachoka and the late Grace Wambui.

Through donations from many benefactors mainly by the school patron, Dr. C. Sheth and through the support of late honorable Njenga Karume, The school relocated to the current site in 2007, after construction of 4 classrooms and administration block an occasion which was graced by the late Prof. George SaitotiĀ  the then minister of Education and the area MP the late Njenga Karume.

Since then, many more buildings have been constructed to provide standard O-Level curriculum. Several other Constructions keep going on to make the school an academic hub. Since the first batch, the school mean score has had an upward trend, maintaining an over all C+ with negligible fluctuations.