▁in ▁central ▁She ff ield , ▁moving ▁to ▁a ▁site ▁on ▁Cav end ish ▁Street ▁in ▁ 1 8 6 2 . ▁ ▁In ▁ 1 9 1 9 , ▁the ▁Sister s ▁moved ▁their ▁living ▁qu arters ▁from ▁Cav end ish ▁Street ▁to ▁Oak bro ok ▁House , ▁a ▁Victor ian ▁m ansion ▁in ▁Ran mo or ▁built ▁in ▁ 1 8 6 0 ▁for ▁Mark ▁F irth , ▁a ▁steel ▁manufact urer ▁who ▁became ▁Lord ▁Mayor ▁of ▁She ff ield ▁and ▁Master ▁C ut ler . ▁ ▁In ▁ 1 9 3 5 , ▁another ▁secondary ▁school ▁was ▁built ▁in ▁the ▁grounds ▁of ▁Oak bro ok ▁House ; ▁in ▁ 1 9 4 8 ▁the ▁two ▁schools ▁am alg am ated ▁to ▁form ▁a ▁girls ' ▁grammar ▁school , ▁Notre ▁D ame ▁High ▁School ▁for ▁Girls , ▁on ▁two ▁sites . ▁ ▁The ▁grammar ▁school ▁was ▁converted ▁in ▁ 1 9 7 6 ▁to ▁a ▁mixed ▁compreh ensive , ▁still ▁on ▁two ▁sites . ▁The ▁school ▁finally ▁cons olid ated ▁onto ▁the ▁Oak bro ok ▁site ▁in ▁ 1 9 8 8 ▁when ▁the ▁Cav end ish ▁site ▁was ▁closed ▁and ▁subsequently ▁demol ished . ▁ ▁Oak bro ok ▁House , ▁which ▁was ▁owned ▁by ▁famous ▁She ff ield ▁steel ▁baron ▁Mark ▁F irth ▁and ▁part ▁of ▁the ▁school ▁since ▁ 1 9 1 9 , ▁is ▁now ▁the ▁school ' s ▁Six th ▁Form ▁block ▁and ▁has ▁been ▁a ▁listed ▁building ▁since ▁ 1 9 7 3 . ▁The ▁main