http://directory.google.com/Top/Kids_and_Teens/School_Time/
An awesome compendium of homework help, subject and age oriented web content. A great listing of education relevant Internet resources.

http://school.discovery.com/students/
DiscoverySchool.com has changed, but it still has tools to help you study, games to challenge your mind, and tons of great clip art to use. In addition, there are nearly a dozen learning adventures that let you explore everything from Ancient Egypt to the Space Station.

http://www.jiskha.com/
Jiskha Homework Help provides the best free homework help services and school assistance directories available on the internet in order to help you learn and improve grades in the classroom. Post questions on the homework help forum, and submit questions to professional experts and teachers. Explore and browse the various school subjects for helpful articles, resources, and links. You can even search for topics that interest you.

http://www.homeworkspot.com/
HomeworkSpot.com is a free homework information portal that features the very best K-12 homework-related sites together with engaging editorial in one high-utility, educational spot. With the help of students, parents and teachers, our team of educators, librarians and journalists has scoured the Web to bring you the best resources for English, math, science, history, art, music, technology, foreign language, college prep, health, life skills, extracurricular activities and much more. For your convenience, we have made every effort to organize these resources into grade-appropriate categories for elementary, middle and high school.

http://www.khanacademy.org/
Khan Academy supplies a free online collection of over 2,200 micro lectures via video tutorials stored on YouTube teaching mathematics, history, finance, physics, chemistry, biology, astronomy, and economics. The Khan Academy also provides a web-based exercise system that generates problems for students based on skill level and performance.

http://www.studystack.com
StudyStack.com strives to help people learn what they want to learn. The StudyStackTM concept was designed to help people memorize information about various subjects. Using the StudyStack web site, you use your computer to display a stack of "virtual cards" which contain information about a certain subject. Just like flashcards, you can review the information at your own pace discarding the cards you've learned and keeping the ones you still need to review.

http://www.calc101.com/
Check your calculus homework! Enter your function to get your calculus derivative or integral with each step explained, automatically and fast.