Shadows can be found easily everywhere around us, so that we rarely find it interesting to reflect on how they work. In order to raise curiosity among students on the optics of shadows, we can display the shadows in 3D, particularly using a stereoscopic set-up. In this paper we describe the optics of stereoscopic shadows using simple schematic drawings. We also describe how to build a very simple demonstration set-up for casting and displaying stereoscopic shadows. Moreover, we also describe a list of student activities that can be used to further raise their curiosity.