A study assessed dimensions of children's reading motivations by giving them a revised version of the Motivations for Reading Questionnaire (MRQ). The MRQ is designed to assess 11 possible dimensions of reading motivations, including reading efficacy, several intrinsic and several extrinsic reading motivations, social aspects of reading, and the desire to avoid reading. Approximately 600 fifth- and sixth-grade children completed the MRQ as part of a larger intervention study designed to increase children's reading comprehension and enjoyment of reading. Analyses of children's responses to the MRQ showed that many of these dimensions can be identified, and measured reliably. Scales based on the different dimensions related positively to one another, and negatively to the desire to avoid reading. Several of the scales related to children's reports of their reading frequency, and to their performance on four measures of reading achievement. (Contains 40 references and 8 tables of data.) (Author/RS)