Purpose: The purpose of this paper is two fold. First, it presents the developmental stages and running modes of K12 Online Schools in China. Second, it illustrates online education practice, its current status, and the use of ICT in online schools. The experiences and lessons learned from the development of the K12 Online Schools are presented, and suggestions are summarized for the sustainable development of the schools. Design/methodology/approach: This study reviews relevant literature and uses questionnaires to collect information from the Beijing No. 4 Online School, which is a representative sample of K12 Online Schools. Findings: K12 Online Schools have experienced three stages: the initial stage, the adjustment stage, and the steady stage. There are multiple modes of running K12 Online Schools in China. The schools mainly deliver their courses through a satellite-based TV net or the internet. The main teaching and learning strategy is still lecturing. Teacher training is critical for improving and assuring the quality of online courses. Practical implications: The rapid development of ICT can propel K12 Online Schools to maturity. However, more emphasis should be put on learner support and teachers' professional development. Originality/value: This article summarizes K12 Online Schools practice and their current status in China. It will help in understanding the current development of online education in China and the challenges it faces. (Contains 3 tables and 1 figure.)