Science
Physical Science
Simple Machines
NeoK12 has activites and videos about simple machines, including a Bill Nye the Science Guy video. You have to register, but the website is free. They also have videos, games, and worksheets for many other science topics.
Simple Machines for Kids is a website offered by AppliancePartsPros.com. It has lots of links for lesson plans for learning about simple machines.
Sound
Discovery Education has a unit study online about sound waves.
The Physics Classroom has a unit about sound for older students.
Physics
HippoCampus offers a physics class online. The animated presentations make the lessons very interesting, even for younger students.
Massachusetts Institute of Technology has Prof. Walter Lewin's Physics lectures on YouTube.
Chemistry
The Periodic Table of Videos, offered by the University of Nottingham, has links to videos about each of the elements. These are fun!
The Periodic Table is an interactive unit for grades 9-12 offered by Interactives.
Apologia Physical Science
Links for Quia flashcards for Apologia Education Ministries' Exploring Creation with Physical Science by Dr. Jay L. Wile
Life Science
General Biology
HippoCampus has free biology classes online. You can choose a textbook, and then watch an audiovisual presentation about each topic. The animations make the lessons very interesting.
The University of California, Berkeley has videos of its General Biology 1A course online.
Apologia Biology
Links for crossword puzzles and Quia flashcards for Apologia Education Ministries' Exploring Creation with Biology (2nd edition) by Dr. Jay Wile and Marilyn F. Durnell
Quizlet also has flashcards for Apologia's Exploring Creation with Biology. I like Quizlet, because you can print flashcards for the vocabulary words.
Cells
NeoK12 has short instructional videos about cells online.
All About Science has a video clip from Unlocking the Mysteries of Life which shows an animation of DNA replication.
Cells Alive! has interactive models of cells.
Nancy Clark, a retired science teacher, has a page on her website about cells which includes experiments, activities, crossword puzzles, and lots of other links about cells.
Animals
National Geographic has interesting videos and articles online about many different animals.
Enchanted Learning has pictures to color and label, articles to read, forms for making reports, and many other resources. You can access the website for free, but if you pay the $20 yearly subscription fee, you can print pages without ads.
All About Birds is an online guide to birds and bird watching that is offered by Cornell University. This site is packed with information about birds! If you look up a bird, you can also listen to a recording of a typical bird song for that type of bird.
Plants
The Arbor Day Foundation has an interactive website for learning about trees.
The Wisconsin Department of Natural Resources also has a website for tree and shrub identification. The Beginner's Tree Identification page is especially helpful for identifying trees and shrubs in the Wisconsin area.
BBC has a game for learning the parts of a flower. You click on each part of the flower, and drag it into the box with the correct name on it.
Anatomy and Physiology
Links for Quia flashcards for Apologia Educational Ministries' The Human Body: Fearfully and Wonderfully Made! by Dr. Jay L. Wile and Marilyn M. Shannon, M.A.:
Quia flashcards for learning the names of the bones of the skeleton
The Digestive System - This is a link to a Quia game about the digestive system. Match the name of the digestive organ to the correct number on the picture.
Crossword puzzle for Joanna Cole's The Magic School Bus Inside the Human Body
Earth Science
Astronomy
NASA has a website about astronomy called StarChild: A Learning Center for Young Astronomers. The site is offered at two different reading levels.
Snowflakes
SnowCrystals.com has lots of information about snowflakes, and beautiful photos of snowflakes. There is also a page with instructions on how to make paper snowflakes that look like real six-sided snowflakes.
Clouds
Web Weather for Kids has activities and games for learning about different cloud formations.
Rocks
Rock Hound has lessons about how igneous, sedimentary, and metamorphic rocks are formed. The site has animations and quizzes.
Interactives has an interactive website about rocks that has lessons about the three main types of rock, how to tell the different rock types apart, and how rocks change from one type into another.