Elementary School Children’s Understanding of Experimental Error

Understanding data variability and potential error sources is essential to a full understanding of experimental science. We propose a typology of error that considers not only the nature of the error, but also the phase in the experiment in which it occurs. We looked at secondand fourth-grade children’s understanding of error, their use of evidence in guiding this understanding, and the role of context in reasoning about error. We found that children could name and recognize sources of error even when they were unable to design controlled experiments. Children used evidence to guide their reasoning, making predictions and drawing conclusions based on the design of their experiments. Children were also sensitive to the context of reasoning: they differentiated the role of random error in relative and absolute measurements. These findings suggest that children understand a wide variety of potential error sources several years before they have acquired the systematic procedures necessary to control and interpret