What it is: The National Security Agency’s Web site for kids wants to find “future codemakers and codebreakers.” (The National Security Agency is part of the Department of Defense; it collects and analyzes secret codes that enemies of the United States might be sending.)
Who will like it: Kids who love brainteasers will spend hours here. Cool characters guide you through activities that include deciphering Morse code and making up codes.
Our favorites: Language Barriers, a matching game where you have to find “hello” in 10 languages, and Makeit@Home! which has home or school projects, including a cipher wheel using a soda bottle.
Homework help: The Student Resources section includes devices used through history to make — and decode — secret messages.
What it is: Based on the popular PBS show, the Web site has just been redesigned with activities, games and puzzles for 8- to-11-year-olds.
Who will like it: This site has something for everyone, including video clips from the show, polls, online games and printable activities.
Our favorites: The “Bugs in the System” game is completely addictive. At first, it seems easy to move the bugs from a room to their correct spot in a graph. But they move really quickly, and if you get too many bugs, you have to change the scale of the graph. “Crossing the River” could best be called “Scratching Our Heads” as you figure out how to get three people across a river in one boat in the lowest number of moves.
Homework help: “Activities” has cool projects, including a wind gauge, a Mobius strip and even fog!
8A Student’s Guide to Global Climate Change
What it is: A site by the Environmental Protection Agency about the causes and impact of climate change.
Who will like it: Kids who think that climate change, pollution and other environmental concerns are a big issue in the world today.
Our favorites: “Calculate your emissions” tells the impact that your actions have on the world. (Turning off the water while you brush your teeth prevents the same amount of carbon dioxide emissions that would be created by driving a car 292 miles.)
Homework help: A short, cool animation clearly explains the greenhouse effect. A “Did you know?” feature on every page offers lots of cool facts you can use to amaze your teachers on your next science project.
— Tracy Grant