The purpose of this study is to analyze underachieving students\' error factors in the
measurement domain of elementary school mathematics, and to help improve their measuring
abilities. In general, there have not been many studies examining error analysis in the
measurement domain as compared to number & operation domains and figure domains. This
study focused on elementary school student\'s measuring ability and feelings of massiveness.
Measurement using units are taught beginning in elementary mathematics, thus this activity has
very important implications for teaching various units, conversion of units, and operation of
units. The other objects of this study were to think about the relation between measuring ability
and feelings of massiveness. According to this study, underachieving students\' feelings of
massiveness is in proportion to their measuring ability. In other words, the underachieving
students\' feelings of massiveness was very low compared with other students. This low
achievement had an effect on the overall learning in the measurement domain. In order to point
out these problems and to improve these errors, this study set up three subject matters: first,
we analyzed the types of underachiever\'s errors in measurement domain and investigate a
relation between measuring ability and feeling of massiveness; second, we reconstructed
teaching contents to correct their errors in the measuring of length and angle; and third, we
prepared the measuring settings to continue length measuring and angle measuring. From this
study, we expect to propose teaching methods to help underachieving students\' errors in the
measurement domain and to explain their failures in the leaning of measurement domain
(length measuring and angle measuring).