Characteristics of students assigned to technology-based instruction John A. Ross,* Tim Sibbald† & Catherine D. Bruce‡ *OISE/UT Trent Valley Centre, University of Toronto, Box 7190, 1994 Fisher Dr., Peterborough, ON K9J 7A1, Canada †OISE/UT Trent Valley Centre, University of Toronto, Box 7190, 1994 Fisher Dr., Peterborough, ON K9J 7A1, Canada ‡School of Education & Professional Learning, Trent University, 1600 West Bank Dr., Peterborough, ON K9J 7B8, Canada Abstract Previous research has examined factors influencing teacher decisions to integrate technology using between-teacher designs. This study used a within-teacher design to compare students who were assigned multi-media learning objects for learning fractions with students taught by the same teachers who were not assigned to the technology. There were two conditions: (1) teachers were asked to limit the number of assigned students to 25% of their class (N = 375 grade 7–10 students) and (2) teachers could assign as many students as they wanted (N = 149 grade 7 students). In the constrained decision setting, students assigned to the technology were more likely than students not assigned to score lower on a fractions achievement test, have dys- functional attitudes towards mathematics learning, have low self-efficacy, exert low effort, and be male. In the unconstrained decision setting, 70% of students were assigned the technology and the only statistically significant predictor was prior achievement. Teachers’ criteria were congruent with research identifying correlates of mathematics achievement and comfort with technology. Keywords Learning objects, fractions, teacher decision making, self-efficacy. Introduction Researchers investigating the integration of technology into classroom instruction have searched for factors influencing classroom use. For example, Tondeur et al. (2008) identified structural and cultural factors operat- ing at the school and teacher level that influenced instructional uses of technology. In our research, we continued the search for factors influencing teacher decision making, examining one type of use (the com- puter as a learning tool) in one subject (mathematics). We focused on the use of computers as a learning tool because classroom integration of technology promotes deeper understanding of mathematical concepts, makes instruction more student-centered, provides students with realistic mathematical experiences, promotes student reflection through interactive feedback and broadens epistemological authority in the classroom (Heid 1997). Previous studies report positive effects for differenti- ated instruction (Odgers et al. 2000; Mastropieri et al. 2006; Reis et al. 2007). Differentiation of instruction has multiple meanings, ranging from variations in instructional materials (e.g. Mastropieri et al. 2006) to a network of plug-in programs, assessments, multiple lesson preparations and shared teaching (e.g. Valli & Buese 2007). In our study, technology was used to differentiate instruction at three levels identified by McTighe and Brown (2005): the software addressed essential skills not mastered by a portion of the class; presented content in a way not previously encountered Accepted: 3 July 2009 Correspondence: John A. Ross, OISE/UT Trent Valley Centre, Box 7190, 1994 Fisher Dr., Peterborough, ON K9J 7A1, Canada. Email: jross@oise.utoronto.ca doi: 10.1111/j.1365-2729.2009.00328.x Original article 562 © 2009 Blackwell Publishing Ltd Journal of Computer Assisted Learning (2009), 25, 562–573