Habitability beyond the Earth is a complex topic that - along with the Drake Equation, star and planet formation, and the co-evolution of our planet and its biosphere - is part of an astrobiology course at the University of Texas at Dallas designed for both in-service and pre-service teachers. The scale of worlds in size and distance from their star is directly related to both planetary evolution and the concept of habitable zones. I will discuss how a 1 to 10 billion scale model of the Solar System inspired by permanent installations at the University of Colorado at Boulder and the National Mall has been extended to exoplanetary systems with Earth-like planets to facilitate discussions of habitable zones, differences in main sequence stellar luminosity by spectral class, differences in planetary systems, “Eyeball Earths”, and more. Links to classroom-tested lesson plans and resources will be provided free to participants.