In today's schools, teachers and leaders must have the knowledge to promote 21st-Century teaching and learning. This resource center provides flexible professional development options for schools and districts focusing on 21st-century learning, through classroom technology use and school-wide reform.
This site is really interesting. I clicked on educators and I was able to search a topic by keyword, grade, as well as state and standard. When the search came up It has numerous additional links to go out to. It really looked like the links had good materials for teachers and kids. The one that I chose had lessons that could be printed out for educators.
We are complementing Salman's ever-growing library with user-paced exercises--developed as an open source project--allowing the Khan Academy to become the free classroom for the World.
Log in to the Khan Academy web application for user-paced practice and instruction
WOW, self pace lessons accompanied by the Khan Academy videos. Works with Google Apps and teachers can become "coaches" for the students to run reports on their progress totally free. Looks like it will grow in math and then to science, just a guess b/c of the Google Sky use. Please check this out especially if you have Google Apps in your district.