THEME:   last word of a phrase is a kind of party   
GOOD ONES:     Wayne's World catchphrase {& theme}   PARTY TIME   
Works in a museum   ART [the noun, not verb]   
Made a point of?   SHARPENED      
BTW:   "Let me help"   WHAT CAN I DO [in a way, but awkward]      
Not doing one's job   DROPPING THE BALL [in a way, but awkward: are these clues designed to be tricky or clever?  I find them neither.]      
Afternoon ora   TRE [apparently mixing English and Italian as my mother did is acceptable]      
"HIP to be Square" has a clever lyric and a catchy arrangement (a bit jazz-like).   
https://www.youtube.com/watch?v=S-Pph3p6zww      RATING:    

Three grins = Loved it; Two grins = Enjoyed it; One grin = A bit bland for my taste; One teardrop = Not much fun