This chapter describes the outcome of the study of moveable paper wheels, so called volvelles, within the Sphaera corpus examined by the research project The Sphere at the Max Planck Institute for the History of Science. The volvelles within the corpus were used for pedagogical purposes and as material models to display movements of spherical objects and underlying astronomical concepts and knowledge. For this, these moveable paper wheels made use of the picture superiority effect, which refers to the brain’s tendency to memorize (moveable, in this case) images more easily than words. Additionally, it was shown how the largest group of volvelles, initially printed in Wittenberg, was reprinted and spread all over Europe, which supports the thesis of an epistemic community existing in Wittenberg. Finally, it was proven that 34% of the known Sphaera editions hold volvelles, which makes the volvelles an important part of the book’s tradition.