Fifth International Conference on Science and Mathematics Education CoSMEd 2013 Penang, Malaysia 11 – 14 November 2013 1 GRADE 6 STUDENTS’ PERFORMANCE ON A MEASUREMENT TASK Siew Yin HO sho@csu.edu.au Research Institute for Professional Practice, Learning and Education, Charles Sturt University, Australia Tom LOWRIE tlowrie@csu.edu.au Research Institute for Professional Practice, Learning and Education, Charles Sturt University, Australia Abstract This paper describes Australian and Singaporean Grade 6 students’ (n=1009) performance on a graphic measurement task. The task required the students to decode graphic information (a rectangular-shaped sticker of a bird positioned along a ruler that was positioned away from the 0-cm mark). Fifty-eight percent of the students gave incorrect responses. Most errors were a result of students: (a) measuring the bird rather than the sticker; (b) confusion about measuring the length of an object not aligned to the 0-cm-mark on the ruler; and (c) encoding their own diagram (graphic) to solve the task. Two main implications were drawn from the study, namely: (1) students had incomplete understanding of the concepts in conservation of length, the zero-point and the identical unit; and (2) the graphic may have hindered students from giving the correct response. Keywords: measurement; conservation of length, zero-point; identical unit, encoding Introduction Measurement of units provides many applications to everyday life. It helps students bridge other mathematics concepts such as area and perimeter. It is also used in the learning of other subjects in school, for example, science, social studies and physical education. Hence, it is of no surprise that measuring is an important mathematical skill in most school curricula internationally. In this paper, the mathematics concept discussed is length. Before defining what length is, one needs to understand the term, “distance”. Distance is the empty space between two points. Length is characteristic of an object and it refers to quantifying the empty space or how far it is between the two endpoints of an object. Thus, length is an important concept in linear measurement. In literature, measuring consists of two aspects: 1) identifying a unit of measure and subdividing (either physically or mentally); and (2) unit iteration, that is, placing that unit end to end (iterating) alongside the object being measured. The hash marks and numerals on a conventional ruler thus represent the result of iteration. Subdividing and unit iteration are “complex mental