This report offers guidance for those shaping policy and designing high school mathematics courses that prepare students to be lifelong users of mathematical ideas. We have reviewed programs designed to improve high school students' understanding of mathematics by incorporating instructional technology effectively into the curriculum. Using criteria backed by research on learning and instruction, we have selected exemplary programs from among those reviewed. We emphasize the teaching of mathematics as a process of inquiry in which students learn to solve complex problems and critique mathematical arguments. We look for uses of computer and communications technology that help students become lifelong mathematics learners who are prepared to meet all sorts of challenges from computing their income taxes to interpreting data on global warming to assessing the risk of a medical procedure. We discuss: (1) Contemporary views of teaching and learning mathematics; (2) Promising uses of technology in learning and instruction; (3) Evolving uses of technology in mathematics; (4) Criteria for selecting exemplary instructional programs; (5) Reviews of programs that meet our mandatory requirements, organized by category; (6) Recommendations of exemplary programs; and (7) next steps. (Author)