This document discusses lessons that can be learned from South Korea's Cyber Home Learning System (CHLS) for online K-12 education in the United States. It provides background on the history of distance education and online learning in South Korea, describing how the CHLS began in 2005 and now serves over 12 million students. The CHLS is an important supplemental learning program that helps reduce costs for private tutoring and provides more equal access to education across regions. It currently has around 10,000 online teachers supporting students.