"Arcademic Skill Builders are free research-based and standards-aligned educational games! Engage and motivate students with our multiplayer and single-player games."
You can see how the planets rotate, you can see the constellations, it is a great visual for teaching astronomy and for teaching about the planets and solar system.
This activity is a scaffolded process of working users through the understanding of fractions beginning with how to divide up an item through the creation of fractions. Would be a good IWB activity.
Teacher Toolbox is an interactive math and reading resource for K-5th grade. There are interactive math applets, math games, free flash cards, interactie whiteboard lessons, reading games stories for kids, professional development resources as well as printables.
This link takes teachers, parents and students to a variety of resources related to literacy. You have to click on a topic of interest and then a list of topics will appear and you select one.