"Kept back as she was by every body else, his single support could not bring her forward, but his attentions were otherwise of the highest importance in assisting the improvement of her mind, and extending its pleasures. He knew her to be clever, to have a quick apprehension as well as good sense, and a fondness for reading, which, properly directed, must be an education in itself. Miss Lee taught her French, and heard her read the daily portion of History; but he recommended the books which charmed her leisure hours, he encouraged her taste, and corrected her judgment; he made reading useful by talking to her of what she read, and heightened its attraction by judicious praise." (Chapter 2)Fanny's accomplishments in the academic subjects of French and History are less important than her mentored reading for shaping her character (her "taste" and "judgment"). The nature of that mentoring is especially interesting. "Fondness for reading" can be "an education in itself" if that reading is "directed" by a sensitive interlocutor whose conversation helps the reader learn interpretive skills. Affection plays a crucial role in Fanny's learning-through-reading as well; she loves Edmund for paying her the attention no one else at Mansfield will, and thus is eager to learn from him and to earn his "judicious praise."
Want to know more? June Sturrock's excellent edition of Mansfield Park published by Broadview Press elucidates the novel's contexts by reprinting excerpts of treatises on manners, conduct, and education, as well as the theatre, religion, estate improvement, and the West Indies.