The purpose of this research was to examine the effect of teacher read-aloud on adolescent learning in science and variation according to individual reading ability. The study gathered both quantitative and qualitative data for analysis from 2 treatment procedures. All seventh and eighth grade students participated in 2 consecutive units of study: 1 unit requiring students to read the science text silently and the second unit providing a teacher read-aloud of all text. The classroom procedures, assignments, and related activities were exactly the same for both treatments. Student learning was measured with pretest, posttest, and delayed posttest concept map scores on each unit of study. A survey administered at the end of the study examined student attitudes toward the teacher read-aloud and served as the source for in-depth interviews concerning preference for or dislike of the teacher read-aloud strategy. A repeated measures analysis suggested both teacher read-aloud and silent reading were appropriate for student learning but results do not support either method as superior over the other. Multiple regression analyses were conducted on the posttest and delayed posttest scores as the dependent measured, had a significant relationship between treatment by reading ability interaction on one analysis. Regression equations constructed for each level of the treatment indicated that as reading ability increases, students received more benefits from the teacher read-aloud procedure. A correlation compared reading ability with attitude toward teacher read-aloud. Seventy-eight of the participants had a positive attitude toward the intervention, with no students reading below the 50th percentile showing disapproval. Interview responses supported these results since all below average readers favor the oral presentation. Overall themes from the interviews offered advantages and disadvantages of teacher read-aloud, suggestions for implementation, and a teacher's perspective on practical applications in science classes.