With the continuous deployment of ICT in K-12 education, strong access but weak uptake has become the greatest challenge for ICT implementation in schools. As the pioneer of China's K-12 educational reform, Shanghai draws our attention in terms of the critical factors and the underlying mechanism of ICT transformation in K-12 schools. The study used questionnaire survey data collected from 2894 Shanghai teachers (971 primary, 990 middle and 933 high school teachers) to investigate the relationships between government ICT policy, school principal e-leadership, ICT implementation in schools, teacher attitudes towards ICT and pedagogical change and changes in student learning. The structural equation modelling results revealed a significant influence of e-leadership by school principals on ICT transformation in schools, confirming the critical role of e-leadership in ICT transformation model. In addition, the higher the school stage, the more personal rather than organisational factors affected the changes in teaching and learning. The findings imply a profound sociocultural and technological dilemma due to the pressure of getting into college and risk-taking in ICT-related educational transformation. The study contributes to our knowledge in terms of a more nuanced ICT transformation mechanism between school stages.