Called the father of modern experimental science, Galileo Galilei was a seventeenth-century Italian astronomer and physicist. He is known for discovering the law of pendulums, using a telescope to view the moons of Jupiter, supporting a Copernican view of the universe, and a famous, but perhaps fictional, gravity experiment from the top of the Tower of Pisa.
The comprehensive Galileo Project from Rice University is an excellent resource for school projects. It includes a biography, a time line, and a gallery of portraits. If you are ready to move beyond the basics, try Science (articles about the scientists and scientific instruments of Galileo's time) and Christianity (an introduction to the inquisition and important church figures.) For links to lesson plans, look in the Library.
The Institute and Museum of the History of Science in Florence provides a rather quirky online exhibit that includes the middle finger of Galileo's right hand. I'm not kidding. "This item exemplifies the celebration of Galileo as a hero and martyr of science. The finger was detached from the body by Anton Francesco Gori on March 12, 1737, when Galileo's remains were moved from the original grave to the monumental tomb built on the initiative of Vincenzo Viviani."
This PBS site is my Galileo pick of the day because it's got both style and substance. Visit for the great articles (such as the biography and a exploration of Galileo's telescope) but stay for the fun interactives, which include animated recreations of several of Galileo's most famous experiments. "A young Galileo is perched atop the Leaning Tower of Pisa. He is in the middle of his famous experiment the one in which he shows, by dropping cannonballs of different weights, that all objects fall at the same rate. It's the kind of story that's easy to imagine, easy to remember, but whether he ever performed the experiment at the tower is debatable."
NASA traces our exploration of the solar system back to Galileo's use of the telescope. "In 1610, Galileo Galilei used a new optical instrument -- known today as a telescope -- to look at the night sky. He discovered several points of light close to the planet Jupiter." Although there are only a few pages here on Galileo, they are well-written and perfect for middle schoolers. Follow the links at the bottom of the article to learn about modern-day space missions.
In 1543, Nicolaus Copernicus published a revolutionary idea: the Sun is the center of the universe and the Earth revolves around the sun. Most of the world didn't believe him, but some sixty years later, Galileo's telescope allowed him to confirm Copernicus' theory and "emboldened him to make public arguments in its favor." The Vatican didn't take kindly to Galileo's views, and a trial resulted. Visit this University of Missouri-Kansas City site to learn what happened, and to explore other famous trials of yesteryear.