The board of governors at Merchant Taylors' Schools in Crosby, north of Liverpool, have given the final go-ahead for the construction of a new £5.5m sports centre.
The sports centre, designed by Buttress Fuller Alsop Williams Architects, will include a dance studio, fitness suite and large indoor space for rugby, football, hockey, badminton and other sports.
Bardsley Construction has been appointed to build the extension will be completed for the new school year starting September 2011.
Located at the Boys' School site, the development will benefit pupils from all elements of the Merchant Taylors' Schools.
Leo Coligan, chairman of Governors, said: "This exciting project underlines our confidence in the future of Merchant Taylors' Schools and their pursuit of excellence in all areas, academic and sporting, and our determination to provide the very best facilities for our boys and girls."