Digital game-based learning is a research field within the context of technology-enhanced learning that has attracted significant research interest. Commercial off-the-shelf digital games have the potential to provide concrete learning experiences and allow for drawing links between abstract concepts and real-world situations. The aim of this paper is to provide evidence for the effect of a general-purpose commercial digital game (namely, the "Sims 2-Open for Business") on the achievement of standard curriculum Mathematics educational objectives as well as general educational objectives as defined by standard taxonomies. Furthermore, students' opinions about their participation in the proposed game-supported educational scenario and potential changes in their attitudes toward math teaching and learning in junior high school are investigated. The results of the conducted research showed that: (i) students engaged in the game-supported educational activities achieved the same results with those who did not, with regard to the subject matter educational objectives, (ii) digital game-supported educational activities resulted in better achievement of the general educational objectives, and (iii) no significant differences were observed with regard to students' attitudes towards math teaching and learning. (Contains 9 tables and 5 figures.)