OMG! Finally someone with taste in music! JUST KIDDING don’t come at me haha 
I can’t really choose one song, so I’ll go with the ones I liked the best from each album + singles.
the Crybaby/Dollhouse era
- Tag, You’re It
- Milk and Cookies
- Mad Hatter
- Cake
Dollhouse was the song that first got me into Melanie, it’s not my favorite though!
the K-12 era
- The Principal
- Strawberry Shortcake
- Lunchbox Friends
- Teacher’s Pet (I know, highly controversial one, but like any of her songs, it’s full of meaning)
the After School era
- The Bakery
- Test Me
- Brain & Heart
They’re in no particular order, I like them all equally! Also, I don’t dislike any of her songs except maybe Soap and Sippy Cup, sorry 
so even if they didn’t make it into my list, I still listen to them all 