▁Harrison , ▁starting ▁off ▁with ▁ 2 1 ▁k ids . ▁Ch orus ▁is ▁dedicated ▁into ▁impro ving ▁vocal ▁technique , ▁ch orus ▁music , ▁music ▁history , ▁theory , ▁and ▁music ▁appreci ation . ▁Stud ents ▁can ▁also ▁take ▁an ▁AP ▁Theory ▁course , ▁or ▁a ▁World ▁Ch oir ▁class ▁which ▁enh ances ▁in ▁music ▁from ▁different ▁regions ▁of ▁the ▁world . ▁There ▁are ▁currently ▁three ▁cho irs : ▁Women ' s ▁for ▁girls ▁in ▁gr ades ▁ 9 - 1 2 , ▁Men ' s ▁for ▁boys ▁in ▁gr ades ▁ 9 - 1 2 , ▁Chamber ▁for ▁boys ▁in ▁gr ades ▁ 9 - 1 2 ▁and ▁any ▁girl ▁that ▁wants ▁to ▁aud ition , ▁and ▁Harrison ▁Sing ers , ▁an ▁all - comb ined ▁cho ir . ▁The ▁ 2 0 1 4 - 2 0 1 6 ▁years ▁has ▁the ▁largest ▁number ▁of ▁men ▁in ▁their ▁cho ir ▁since ▁the ▁start . ▁ ▁Gu itar ▁The ▁other ▁new ▁department ▁that ▁opened ▁with ▁the ▁ 2 0 0 8 ▁expansion , ▁Gu itar ▁is ▁dedicated ▁to ▁helping ▁the ▁basic ▁and ▁advanced ▁knowledge ▁in ▁Gu itar ▁playing , ▁impro vis ation , ▁theory , ▁and ▁technique . ▁Stud ents ▁in ▁Gu itar ▁are ▁also ▁el ig ible ▁for ▁the ▁AP ▁theory ▁course , ▁which ▁involves ▁a ▁rig orous ▁curr icul um ▁in ▁theory , ▁sight ▁reading , ▁and ▁composition . ▁ ▁P iano ▁An ▁original ▁department , ▁P iano ▁enh ances ▁knowledge ▁in ▁basic ▁and ▁advanced ▁skills ▁in ▁piano ▁playing