Many believe that girls lack the confidence and motivation to persist with computers when they face a challenge. In order to increase the number of girls and women in information technology careers, we need a better understanding of how they think about and solve problems while working on the computer. In this article, we describe a qualitative study of 126 middle school girls who designed and programmed computer games in an after-school and summer program. Using data from electronic notebooks, we describe how girls thought about the problems they had while programming their games and the strategies they used in their efforts to solve them. Audiotape transcripts were also coded to show how girls talk about challenges and the steps they take to address them when programming a game on the computer. The findings are interpreted in terms of how to promote information technology fluency starting in middle school. (Contains 3 tables.)