provides curriculum guides for using real scientific data to investigate earth processes. Each guide focuses on a topic (sea level, water quality, and El El Nino) and starts with a question: How are sea levels monitored and measured? How is water quality monitored? How does El Nino really work? (National Oceanic and Atmospheric Administration)

includes lesson plans, tutorials, and role playing simulations to help students from middle school up learn about dozens of topics -- taxpayer rights, the history of taxes, indirect taxes, progressive and proportional taxes, exemptions, dependents, education credits, earned income credit, how taxes influence behavior, the politics of taxes, your first job, and more. It also includes 14 self-paced modules offering a step-by-step approach to tax preparation. (Internal Revenue Service)