This paper reports on a preliminary pilot study investigating the mathematical modeling capabilities of an interactive, iconic programming environment called Squeak. Developed by Alan Kay and his associates (see http://www.squeakland.com), Squeak is a media authoring tool that allows students to create sharable and modifiable representations of their ideas using a user-friendly set of graphical and programming tools that are embedded within the environment. Six grade nine business technology students created dynamic representations of their ideas about the mathematical concept of slope by designing and programming an instructional simulation aimed at helping grade six students better understand slope. Early results suggest that: 1) ideas presented in Squeak are inherently improvable because project construction is visible to and modifiable by any user; 2) diverse ideas can be easily shared by the learners either by uploading the file to an online database or through the built-in sharing capabilities in the Squeak environment; and, 3) problems that arise in Squeak are authentic and real as students are able to generate their own ideas and representations of a problem and are not bound by pre-determined graphical or representation parameters. Results also point to the integrated use of Knowledge Forum and Squeak as a potential means to resolve noted difficulties in establishing and maintaining knowledge building communities of practice in mathematics education by providing students with the tools to adequately represent mathematical ideas and facilitate online knowledge building discourse.