If toddlers read the books or the books are read to them, when the child later takes up the skill in question (painting and writing are the ones I'm aware of), they get a boost to the skill - they'll usually start at level 3. The toddler books are all in the same bookcase at the SV library.
Also, on the subject of wanting to read a large number of books, I found out that recipes count. So if your sim has the cooking skill, there's another option.