From the Sabertooth tiger to Socks the Cat, felines have been prowling the planet for thousands of years. And they haven't changed much in all that time! The cat is one of nature's perfect animals, "done right the first time." See the cat world from the inside out (skeletons and all!) at National Geographic's "Plans for Perfection": www.nationalgeographic.com/features/97/cats . This site has the science behind the world's most glamorous predators.

It's time to get slimed! Slither out to http://yucky.kids.
discovery.com and join Wendell the Worm and his human sidekick Dora as they explore the living sciences through cockroaches, earth worms and the mysterious human body. From sneezing and snoring to bug bites, this site covers everything that's gross and yucky. The site has plenty of sounds, videos and games to keep you scurrying about, and you can send gross e-cards to your friends online, or hang out with Ralph the Roach at Bug World.

The legendary albatross, often seen swooping down on ocean liners and gliding over beaches, is now the subject of a fascinating Web study. The Albatross Project allows you to take flight with these big birds via satellite and join them in searches for food and fun. Take a flight of fancy to www.wfu.edu/albatross . Once here, you can do science in real time, tracking the animals along the Pacific Ocean on maps. Meet your fellow kid scientists from around the world, who are making exciting discoveries of their own. The site has fascinating photos and descriptions too. If bird is the word, the Albatross Project is the coolest winged site on the Web.

It's time to answer the call of the wild at the National Zoo. From movie clips to Web cameras, this electric zoo contains an awesome display of animals from around the world. Just leap like a gazelle over to http://nationalzoo.si.edu and play games, check out an endless photo library, and track elephants via satellite. You'll follow researchers around the globe as they observe the antics of the ever-rowdy orangutans and gorillas. There's even a births page, where you can visit rhino calves and a baby giraffe. They are soooo cute!

Sure to be one of the "yuckiest" sites on the Internet, Cockroach World nests in the heart of the World Wide Web. Crawl along for a day in the life of the cockroach or check out the cockroach "Tall Tales Forum." Here, roach experts exchange stories of the good, the bad, and the ugly. You can take the "cockroach quiz" and test your knowledge of these creatures. Don't forget to bring a big can of bug spray and your favorite cockroach tale to http://yucky.discovery.com/noflash/roaches .