This chapter proposes the idea of books as objects and gives a brief introduction to paper instruments as objects of research. The paper instruments examined here are volvelles, which are moveable paper wheels from early modern textbooks that were printed together with the text of the book and installed by the reader when needed. These wheels could either work as amusement, show information, enrich a text, or help with understanding and calculating complex phenomena. The book De sphaera by Johannes de Sacrobosco existed as a university textbook before the “golden age” of volvelles in printed books, but began to contain volvelles in some editions during the early modern era. It thus provides a helpful place to investigate possible ideas behind the concept of volvelles for pedagogical purposes in the early modern era.