Educational video games can impose high cognitive demands on its users. Two studies were conducted to examine the cognitive process involved in playing an educational digital game. Study 1 examined the effects of users' working memory capacity and gaming expertise on attention and comprehension of the educational messages. The results showed that gaming experts seem to benefit more from having a higher working memory capacity when processing information from the game. However, gaming experts' available working memory did not predict better comprehension. Instead, non-experts' available working memory predicted better comprehension. Study 2 further examined whether these results were caused by insufficient working memory allocation or different attention focus between gaming experts and non-experts. The findings suggest that gaming experts approach the game differently from non-experts, focusing on familiar features and overlooking unfamiliar (educational) information.