The online educational module "Why Does a Light Bulb Burn Out?" is an inquiry-based introduction to the concepts of materials and material properties through the interactive exploration of the life of the incandescent light bulb that students use every day. The module offers an exploration of the history of the light bulb, its components, and important filament properties. Students discover the relationship between temperature and incandescence, along with electrical power and resistance through interactive Java applets. Then students "invent" their own filaments through virtual temperature, performance and longevity tests of a variety of candidate materials. Next, students follow the filament aging process using scanning-electron/atomic-force microscopy images. The module culminates in students designing their own materials experiments using SPM Live! online at http://invsee.asu.edu. Student evaluations indicate students both enjoy and learn effectively using the module.