A great number of technologies and tools have been developed to support science learning and teaching. However, science teachers and researchers point out numerous challenges to implementing such tools in science classrooms. For instance, guidelines, lesson plans, Web links, and tools teachers can easily find through Web-based search engines often do not reflect the goals of science education (National Research Council, 1996, 2000) but provide a typical cookbook style activity. Research also shows that one of the major challenges for teachers to implementing well-designed technology tools in science classes is the lack of time, resources, and support. In response to the challenges, this article provides an overview of a theoretical framework for technology integration, discusses practical guidelines and principles for technology integration for science classrooms, and presents examples of Web-based technologies available for integration in science classes. (Contains 1 table and 2 figures.)