This video segment adapted from NOVA shows how Galileo, using his newly developed refracting telescope, observed four of Jupiter's moons, the first astronomical bodies to be discovered since ancient times.

In the early 1600s, most people believed that the Sun revolved around a stationary Earth. This video segment adapted from NOVA tells how Galileo proved that the Sun, not Earth, is at the center of our universe.

This video segment adapted from NOVA shows how Galileo used his telescope to carefully observe and study sunspots.

This illustrated timeline from the NOVA Web site turns back the clock to the late 1500's to relive the dramatic life of one of the world's most renowned scientists.

Gapminder collects hundreds of statistics related to global economic, health, and social development and analyzes the relationships between them across different countries and time (a few indicators go back to 1800).

This video segment from Between the Lions features the Knights of Blending Fields demonstrating an important element of phonemic awareness: blending word parts to make a word.

Part of a series exploring the biotechnology of gene therapy. This section takes a look at some of the challenges faced in gene therapy and complications that have resulted during trial research.

Provides much general information and detailed facts about the sparsely populated Central American country of Belize.

Much historical information and current facts about Chile are given in this well organized and detailed site. Quick facts are displayed in easy to read charts.

Comprehensive site that gives you "Facts at a Glance" or more in-depth information about such topics as geography, people, economy, climate, or foreign relations.

It's easy to explore the Central American country of Guatemala through "Facts at a Glance." Discover information about geography, culture, economy, government, climate, and more.

Read about Jamaica's economy, government, history, or people either as a quick fact or more expanded version at this very comprehensive site.

A detailed and comprehensive resource for finding much information on Paraguay. Organized by quick facts in chart form or longer commentaries.

Read about Uruguay's economy, government, history, or people either as a quick fact or more expanded version at this very comprehensive site.

This activity will help students understand the relationship between the slopes of parallel and perpendicular lines.

Discover how historians use newspapers and learn about the development of the modern newspaper. Get answers to many questions about different newspapers.

A guide to dissecting official documents. Learn how to find the author of documents, the primary audience, and other important information.

Review the text George Washington's first inaugural address given on April 30, 1789. RI.11-12.8 seminal U.S. texts

Calculate the Area of a Trapezoid This Concept Handheld Software Application reviews the definition and area formula for the rectangle, square, parallelogram, triangle, trapezoid, and circle.

Explore probability theory with interactive animation that simulates the rolling of dice, tossing of coins and generating random numbers. Evaluation options include bar graphs, table of trials data, settings for specifying the number of trials, ways to collect data and weighting. In addition, students can export data for further exploration.