Atticus' Perspective: Atticus believes in letting his children grow and experiment. He raises them to be curious and non-judgemental. He also believes that children deserve to be educated and have their questions answered, as he explains to Jack (90).
Alexandra's Perspective: Alexandra believes in keeping children safe and adhering to the social customs appropriate for them. She often approaches Atticus, particularly about Scout's attire or behavior.
Atticus does the best he can to combat Alexandra both directly and indirectly. He gently teases her for things like her obsession with heredity and morals (131), explains her perspective and intentions to a frustrated Scout (84), and when necessary, clearly indicates his displeasure at what he sees as Alexandra overstepping her boundaries (83).
In the end, Alexandra does transform as a character and comes to better accept the openness that Atticus practices and has instilled in his children. However, they never truly see eye to eye when it comes to exactly how Scout and Jem should be raised.