Background: Drawing on theories of purposeful reading, this study explored task conditions that support fifth graders' selective reading of documents in order to answer questions. More specifically, we investigated whether promoting students' elaboration of their task model increases task performance. Methods: Participants had to answer series of questions by searching documents for the relevant information. Half the participants received a task model prompt, and half received a control prompt. Participants' eye movements were recorded during text search, in order to investigate more precisely the effect of an enhanced task model. Results: Participants provided more correct answers in the task model condition than in the control condition, but there was no difference in response time. Unexpectedly, eye movement analysis did not reveal any differences between conditions concerning the number of visits and visit time to relevant and irrelevant areas of the document. Conclusions: A better representation of the information to be searched facilitated students' identification of relevant information. Unexpectedly, however, the task conditions did not result in any significant difference in students' patterns of document search.