This study examined the effect of embodied action on children's conservation reasoning by comparing performance on four classic Piagetian conservation tasks -- length, mass, liquid, and quantity -- under embodied and non-embodied conditions across four age groups. Unlike traditional conservation tasks, which involve passive observation (non-embodied), the embodied condition required children to actively engage through hands-on manipulation, thereby fostering active participation. The study involved 460 children aged 4 to 7 years. Results indicated that children consistently performed significantly better in the embodied condition across all task types. Further analyses revealed that the advantage of embodied participation did not significantly differ across age groups or tasks, although the effect showed a slight, non-significant decline with age. These findings highlight a stable and robust benefit of embodied action in supporting children's understanding of conservation concepts and broader cognitive development. The study offers empirical support for embodied cognition theories and provides practical implications for early childhood education.