Question about Harry Potter?

Yes I noticed that. The only person who is really mentioned in this way is Neville who is a professor at Hogwarts, but there is no indication as to what he did to get there. Realistically there wasn't that much time when Harry wasn't at school and I would have expected him to go back and finish his education, but as you say there is no mention that happens.

Ron and Harry "revolutionize the auror office" of the Ministry of Magic and Hermione "rises high in the ranks of the Dept. of Magical Law Enforcement" (in other words, she becomes the equivalent of a lawyer). JKR revealed these things in an interview within weeks of the release of Deathly Hallows. It will likely be part of the Encyclopedia that she's doing as well.

J.K. revealed what happened to Harry and his friends only during interviews... so if you search in the internet or read a section about Harry Potter in wikipedia.org, you will find out what happened to the other characters... J.K. Rowling did not add them in the book because i think she would just reveal them in interview...