Recognizing where action units begin and end is an early-developing skill that supports inferences about goals motivating others' action. One notable feature of goal-directed action is that segments are organized hierarchically. That is, action is interpreted as structured with respect to the goals and sub-goals of an actor, which can be recognized as corresponding to coarser- and finer-grained action units respectively. We report on the success of adapting a nonverbal paradigm to index hierarchical action segmentation in a developmental population. Results indicated that 3- and 4-year-old children, similar to adults in past studies, responded to segment boundaries with surges in attention that varied according to event granularity (e.g., fine- vs. coarse-grained). This effect was seen most strongly in children displaying superior memory for the events.