The role of gesture memorability in young children’s acquisition of Piagetian conservation concepts remains underexplored, despite growing evidence that co-speech gestures enhance learning. This study examined whether gestures rated as memorable by adults—improve 5- to 7-year-olds’ understanding of liquid conservation and their ability to generalize knowledge to length conservation tasks. Using a between-subjects design, 25 children (M age = 5.84 years) were randomly assigned to view instructional videos featuring either highly memorable (n = 11) or less memorable (n = 14) gestures. Participants completed pretests and posttests assessing liquid and length conservation understanding. Results revealed significant improvements in liquid conservation accuracy for both groups, with no significant difference in learning gains between conditions. A repeated-measures ANOVA confirmed a main effect of time and group, but no interaction, indicating comparable rates of improvement. Age significantly predicted learning gains, with older children benefiting more from instruction. Transfer to length conservation tasks was modest and nonsignificant. While gesture-supported instruction significantly facilitated learning, adult-rated memorability did not enhance its effectiveness, suggesting that children may process gestures differently than adults. These findings underscore the value of gesture-based teaching in early childhood education, emphasizing that even “forgettable” gestures can foster conceptual understanding.