A learning object is an interactive web-based tool that supports learning by enhancing, amplifying, and guiding the cognitive processes of a learner. To date, no formal research has been done on the use of learning objects in secondary school science classrooms. The purpose of this study was to evaluate the use of learning objects developed for high school students in areas of biology, chemistry, or physics. The evaluation metric used to assess the benefits and quality of learning objects was theoretically sound, reliable, and partially validated. Two thirds of the students stated they benefited from using the learning object. Teachers confirmed that learning objects were beneficial to student learning and that they would use them again. Students benefited more if they were comfortable with computers, the content was perceived as being useful, instructions were clear, and the theme was fun or motivating. Students appreciated the motivating, hands-on, and visual qualities of the learning objects most. Computer comfort and learning object type, but not gender, were significantly related to learning object quality and benefit. (Contains 4 tables.) [Appended to this document are: "Appendix A. Learning Object Survey for Students," and "Appendix B. Learning Object Survey for Teachers."]