This research investigated the effects of different pedagogical approaches on the learning of length measurement in kindergarten children. Specifically examined were the pedagogical approaches of guided instruction, center-based learning, and free exploration in the context of a play-based learning environment. This mixed design research was implemented in three different classrooms--with one classroom functioning as a control setting. Results suggest that neither guided instruction nor center-based approaches influenced learning more so than free exploration. Older children did better on the measurement tasks which suggests that age or a developmental progression, rather than the pedagogical approach, is more influential when learning how to measure. More children, regardless of grade, showed a preference for using rulers, albeit the older children were more accurate in their use. Education implications are discussed.