' s ▁school ▁when ▁she ▁was ▁twelve . ▁At ▁school , ▁she ▁met ▁two ▁lif el ong ▁friends , ▁Julia ▁Reb e cca ▁Rog ers , ▁nick named ▁" D olly " ▁and ▁Elizabeth ▁King , ▁nick named ▁" B ess ie ." ▁Both ▁Dol ly ▁and ▁B ess ie ▁were ▁from ▁well - known ▁families ▁associated ▁with ▁the ▁Gar rett ▁family ▁in ▁Baltimore . ▁Dol ly ▁was ▁the ▁daughter ▁of ▁a ▁steel ▁magn ate ▁and ▁became ▁the ▁legal ▁w ard ▁of ▁John ▁W . ▁Gar rett ▁after ▁her ▁father ' s ▁death . ▁B ess ie , ▁from ▁a ▁famous ▁Qu aker ▁family , ▁was ▁the ▁daughter ▁of ▁an ▁associate ▁of ▁Mary ' s ▁father . ▁Mary ▁was ▁initially ▁excited ▁about ▁school ▁life ▁and ▁enjoyed ▁it , ▁but ▁she ▁gradually ▁got ▁b ored ▁because ▁of ▁her ▁school ' s ▁conserv ative ▁st ances ▁toward ▁girls ' ▁education . ▁The ▁school ▁principal , ▁who ▁once ▁had ▁a ▁very ▁good ▁relationship ▁with ▁Mary , ▁believed ▁" in ▁cultiv ation , ▁not ▁in ▁college ." ▁Also , ▁the ▁school ▁restricted ▁girls ▁from ▁studying ▁science . ▁In ▁response ▁to ▁the ▁restrict ive ▁school ▁policy , ▁the ▁three ▁girls ▁formed ▁their ▁own ▁study ▁group ▁to ▁learn ▁bi ological ▁science , ▁and ▁disse cted ▁a ▁rat ▁to ▁everyone ' s ▁horror . ▁Dis app oint ed ▁with ▁the ▁lack l uster ▁experiences ▁of ▁school ▁education , ▁Mary ▁quit ▁school ▁at ▁age ▁sevent een ▁and ▁never ▁returned ▁to ▁school ▁in ▁the ▁following ▁years . ▁She ▁preferred ▁to ▁teach ▁herself