This study is an exploratory study of the relationship between collaboration and mathematics and game outcomes in a video game aimed at teaching concepts related to rational numbers. The sample included 243 middle school students who played the video game either with one partner or individually for 40 minutes. Results suggest that participants with high and low prior knowledge benefit from different conditions during gameplay. Participants with low prior knowledge tend to perform better on math outcomes by working collaboratively and participants with high prior knowledge tend to perform better on math outcomes by working individually. These results are similar to prior findings from classroom research which indicates that collaboration is more effective for low-performing students. These results have implications for designing game environments for low-performing students. Appended are: (1) Math Assessment Items; (2) Background Questions; and (3) Missing Data Analysis. (Contains 3 figures and 10 tables.) [This paper was supported under the Educational Research and Development Centers Program.]