Student use of computers and the internet has increased rapidly in recent years. Teachers ask what types of learning experiences can be facilitated by using the internet in their classrooms (NSBF, 2007). Various surveys of U.S. teachers on internet usage report that having students use the internet for research and information gathering purposes is its most common use (Becker, 1999; Mistler & Songer, 2000; NSBF, 2007). Although use of the internet is popular among educators and students, the theoretical and empirical foundations for its use have not been firmly established. This study investigates the use of the World Wide Web (www) as a research tool to promote self-directed learning of ozone for fifty-two middle school students. Performance of pre-and post-tests were used to determine the effectiveness of www in enhancing students' understanding about ozone; attitude questionnaires were used to ascertain positive/negative effects on student learning using the www. The results showed many positive aspects of using the internet for self-directed learning of ozone, including significantly increased student understanding of abstract science concepts and motivation in taking responsibility and control over one's own learning.