Scout is not happy with Calpurnia in the early chapters.
Our battles were epic and one-sided. Calpurnia always won, mainly because Atticus always took her side... and I had felt her tyrannical presence as long as I could remember. (Chapter 1)
Scout was particularly angry with Cal after she was punished for being rude to Walter Cunningham Jr. when he visited for dinner.
I told Calpurnia to just wait, I'd fix her; one of these days when she wasn't looking I'd go off and drown myself in Barker's Eddy. (Chapter 3)
But Scout comes to see the good side of Cal, and she is so impressed with the housekeeper after their visit to First Purchase Church that Scout wants to visit Cal at her own home in the Quarters. Cal serves as a surrogate mother to Scout and Jem, and Atticus is quick to point out to Alexandra that Cal has
"... never let them get away with anything, she's never indulged them... and another thing, the children love her." (Chapter 14)
Calpurnia has previously taught Scout to write cursive, and she does her best to teach Scout about manners, how to treat guests, and how to serve refreshments to a room full of ladies. Cal keeps an eye on the children when Atticus is absent, setting strict "summertime boundaries" in the neighborhood, and she impresses the kids with her "modest double life" and "command of two languages."