MVC Design: How do we design CRUD for attached components?

Supposing I have three classes: Student, Teacher and Document. Each instance of Student or Teacher can have certain Docu开发者_StackOverflowments attached to itself. My question is how to have CRUD for this, as I want that the admin should be able to attach/detach/update/delete documents for Student, Teacher or any other class. Document attachment, also involves upload of documents.

While designing this (this is my first web experience), I seem to fight the stateless paradigm, as I expect my repository to update when a document is changed, but it does not, when I return from the Document Management Page to the Index of Repository.