Throughout To Kill a Mockingbird, Atticus teaches his children valuable lessons. To what extent are these lessons exemplified by their father?

One of the many things that makes Atticus such a good father is that he always practices what he preaches. He always sets a good example to his children, even if it's sometimes a little difficult for them to follow. Arguably the most important value that Atticus teaches Scout and Jem is empathy, the ability to put yourself in other people's shoes. Atticus doesn't simply teach empathy, he actually lives by it.
An example of this comes in the case of Mrs. Dubose. Scout and Jem—and probably most readers—see her as just a mean, racist old lady who yells at the Finch children each time they walk past her house, but Atticus expresses his great admiration for her bravery in trying valiantly to combat the ravages of drug addiction. Indeed, he says that Mrs. Dubose is the bravest person he ever knew. Mrs. Dubose doesn't spare Atticus from her smack talk whenever he walks past her front porch, but, ever mindful of the value of empathy, Atticus simply doffs his hat politely and says good morning to a sick old lady in the grip of drug addiction.