Online learning continues to grow rapidly across the United States and the world, opening new learning opportunities for students and families. Informed estimates put the number of K-12 students in online courses at over 1 million, as parents and students are choosing online courses and schools for a variety of reasons that grow out of their individual needs. They may seek courses that otherwise would be unavailable at the local school; options to learn at the student's own pace; or accelerated coursework or a class to make up for lost credit. Students who have benefited from virtual schooling include those who have not had success in the traditional school setting, those who wish to learn in a manner that is individualized to their own learning style and pace, with medical conditions that make traditional schooling difficult, teen parents, student athletes, performers and children of military personnel who move frequently. In addition, some states now require an online learning experience as a condition for high school graduation, and even absent this requirement, online courses help prepare students for college and career. Most universities have embraced online learning and many employers use web-based technologies to teach workplace skills. With this growing interest from students and parents, the number of online learning providers continues to grow as well, ranging from state virtual schools, to online charter schools, to the student's district of residence. These options may be public or private, full-time or supplemental, fully online or a blend of online and classroom instruction, creating a potentially bewildering array of options from which students and parents can choose. This guide will assist parents in understanding what online learning is and in selecting the right online school, program or course. (Contains 8 footnotes and 1 figure.)