This study aims to explore the implementation and challenges of China's national online education strategy - "Suspending Classes Without Stopping Learning" (SCWSL) - during the COVID-19 pandemic from the perspective of children and their parents. Altogether 28,334 children (aged 6-8 years) and their parents were randomly sampled from nine cities in five provinces of China, and a mixed-method design involving a questionnaire and interviews was used. The results indicated that: (1) most children had participated in online education characterized by wide-ranging content, teacher-led interaction, and rich learning platforms; (2) online education had an effect on children's physical and mental health; (3) parent pressure was at a medium to high level due to online education; and (4) parents perceived that offline education was more effective than online education, and this perception varied significantly between geographical regions, living areas, and school types. These findings reveal that the sudden implementation of nationwide online education created many challenges, and also provided practical implications for countries carrying out online education in the post-pandemic era.