Engagement is a necessary condition for learning, and previous studies have shown that engagement can be significantly affected by changing the presentation of game elements within an educational game. In a three condition controlled experiment, we examined how changing the presentation of the data elements referred to in a game's goals would influence the purposefulness of the goals and thereby affect players' motivation to achieve them. A total of 121 self-described programming novices were recruited online to play the game. We found that 1) those using vertebrate elements completed twice the number of levels compared to those using inanimate elements, 2) those using vertebrate and invertebrate elements spent significantly more time playing the game overall compared to those using inanimate elements, and 3) those using inanimate elements were more likely to quit the game, especially on difficult levels. These findings suggest that the presentation of game elements that influence the purposefulness of goals can play a significant role in keeping self-guided learners engaged in learning tasks.