Math Snacks animations and support materials were developed for use on the web and mobile technologies to teach ratio, proportion, scale factor, and number line concepts using a multi-modal approach. Included in Math Snacks are: Animations which promote the visualization of a concept image; written lessons which provide cognitive complexity for understanding; and active, situated learning activities to facilitate memorable experiences to deepen comprehension. This pilot study compared pre-post test gains for 460 sixth and seventh grade students enrolled in nine different classrooms. In five of the nine classrooms, teachers utilized the "Teacher Guide: that corresponded with the five Math Snacks animations and one game and in four classrooms teachers used the same Math Snacks animations and one game, but were free to develop their own lessons using available online resources. Results showed moderate and significant pre-post test gains for all six grade students. However, significant gains for seventh grade students were shown only for classrooms where the "Teacher Guide" was used. While it appears that the use of "Teacher Guide" is useful only for seventh grade, such a conclusion is premature given the small number of classrooms and the exploratory nature of this investigation. Further analyses of moderator variables (e.g., instructional fidelity, learner characteristics) are certainly necessary.