Various forms of virtualization play key roles in the construction and usage of diverse system artifacts ranging from modern compilers to hardware migration to mobile computing. Virtualization is also a powerful concept on cognitive grounds, requiring considerable abstraction skills and modeling abilities. We present a methodology, a software tool, and a set of instructional resources designed to expose students to virtual machines, focusing on both abstraction and implementation issues. An early version of our methodology appeared in a book form [4] in which we describe how to build a complete computer system - hardware and software - in one semester. Recently we've re-written our VM emulation software and consolidated all our VM materials into a web site that supports a stand-alone module on virtual machines [5]. This module can be plugged into many system-oriented CS courses. All the resources that we present are freely available in open source and are presently used successfully in several universities.