Fostering young children’s computational thinking (CT) has garnered global interest as it aligns with the cultivation of twenty-first-century skills. Previous studies have focused on physical, virtual and hybrid kits with virtual programming blocks, but rarely explored the use of hybrid kits that combine virtual sprites and physical programming environments. We conducted a quasi-experimental study to investigate the effect of using a hybrid programming kit on young children’s CT. Furthermore, we explored the characteristics of children’s programming engagement and the instructional strategies employed by teachers through video analysis and interviews. The results showed that: (1) children’s CT in the experimental group significantly improved, compared to that of peers in the control group; (2) children’s programming behaviour demonstrated a change from ‘action preceding thought’ to ‘thought preceding action’ and from ‘relying on trial and error’ to ‘active debugging’ with the support of teachers; (3) teachers used multiple strategies to support young children’s programming. These findings further indicate the importance of introducing programming in early childhood education and emphasize the critical role that teachers play in supporting young children’s learning of programming.