IXL is the Web's most comprehensive math practice site. Popular among educators and families, IXL provides unlimited questions in more than 2,000 topics. An adaptive learning system, featuring games and awards, inspires students to achieve.
National Geographic Education brings geography, social studies and science to life. Using real-world examples and National Geographic's rich media, educators, families, and students learn about the world and the people in it.
Smithsonian's History Explorer was developed by the National Museum of American History in partnership with the Verizon Foundation to offer hundreds of free, innovative online resources for teaching and learning American history.