Perceiving (such as seeing) and representing (such as drawing and talking about what one perceives) is fundamental to chemical education. The purpose of this study was to gain further insights and understanding into selected students' representational competence in chemistry through student-generated representations (SGR). In the mixed model design of a larger study, a purposive sample of nine students with three different levels of representational competence were selected. Using semi-structured interviews, three different substances were shown, one at a time, to each student who were then asked to use drawing to represent the substance and to explain the drawing(s). Essential aspects of the SGR expected for each substance were audited and tabulated. Similarities and/differences in representations of the different substances among the students were noted, analysed and compared. Only the data from the high and low groups were included in this report. Findings revealed SGR as a valuable research tool to explore in depth students' representational competence in chemistry.