Organising and representing grouped data.

Two classes of Year 8 students were asked to organize and represent sets of numerical data with large variation of scores, to determine the extent to which the students had learned to produce grouped data and represent them in displays such as a histogram (as stated in the current Queensland syllabus for Year 7). Analysis of the students’ responses in terms of a statistical-thinking framework revealed wide variation in students’ ability to re-organise the data and represent them in organised graphs. Only 21% of students were able to complete the task successfully. Interviews with other students indicated that a little prompting in terms of grouping the data assisted many to produce grouped data with convenient interval sizes. The results of the study have implications for the teaching and learning of the organisation and representation of grouped data.