We selected a sixth grade student to participate in this study. Prior to remedial instruction, the subject did not understand the concept of proportionality and used ratio formulas excessively to solve problems without any meaning on it. In addition, he could not employ multiple representations to explain his solutions. Using an electronic whiteboard and Geometer’s Sketchpad (GSP) to design the dynamic multiple representations for proportional scenarios in remedial instruction induced the subject has better understanding of proportions as well as a better grasp of the linear relationship between two variables. In the final test, the subject was able to use multiple representations to solve problems and check his calculations, therefore increasing problem solving accuracy.