This document presents first-hand experiences of teachers and students using the Internet in K-12 math and science, as well as articles on getting the right hardware, choosing an Internet service provider, designing an online project, and fostering acceptable use. Chapters include: (1) "Something in the Air" (Linda Maston): a computer-assisted environmental investigation; (2) "Penumbra" (Greg Lockett): a cooperative astronomy project that led to one young woman finding friendship and a new mode of self-expression; (3) "Tall Shadows" (Karen Nishimoto): study of the Earth's circumference using the Internet; (4) "Pedagogically Speaking" (Bill Barnes): an online class for fourth through eighth grade math teachers examining the best kinds of cooperative activites; (5) "Hoop Happenings" (Caroline Brennan and Joanna Yantosh): math problem solving via e-mail between elementary and middle school children and college students; (6) "Confessions of a Fourth Grade Newbie" (Glenn Lidbeck): a multi-school project measuring the magnetism of the Earth at different locations using e-mail exchanges between international students; (7) "Desert Studies" (Susan Hixson): a team-taught virtual field trip; (8) "Of Wind and Weather" (Kristine Mueh): developments in teaching style through experimentations with new activities and technologies; and (9) "Expeditions to Mount Everest" (Rory Wagner): the benefits and limitations of using the Internet in project-based science as found by high school students studying earthquakes. Sidebars provide information on tools; online educational resources; and sample projects. (AEF)