Some of my favorite resource links, in no particular order:

Online QR Lab -You've seen them, those little squares of seemingly random squares on ads, windows, and books. They're actually Quick Response (QR) codes, and they're a great way to communicate. By scanning them with their smart phone, the code takes the user to a web site or other location for more information. There are many applications to the school and classroom. Thanks to Violet Croote and her students at Vermont's Green Mountain Central School District for this one.

Lesson Planet - One of the thousands of sites that provide lesson plans and about everything else you need to organize and deliver your curriculum, and to my mind one of the best. There is a low cost membership required, but it's likely worth the time it will save you.

Worksheet Library - The name pretty much says it all. Worksheets, graphic organizers, all the little pieces that take time but are such an important part of your practice.

Dangerously Irrelevant - Oh yes, I love this site by Dr. Scott McLeod. Although he focuses on Iowa (he teaches at Iowa state), his "ruminations" are insightful and, quite frankly, brilliant. Read his stuff, follow his leads, and I guarantee you will see a difference in your classrooms and schools. Warning - if you're not preparing your students for the 21st Century, he WILL take you to task for it.

NASA Quest - A fantastic way to connect with the missions and people of everyone's favorite space agency. Really great projects here, but some of the downloads are HUGE. You can make a very long project out of some of these.

Questgarden - a terrific resource for developing online lessons based on problem-based inquiry. Here's one you can use right now: A Nation of Immigrants. Precede the WebQuest with a short classroom exercise: A Nation of Immigrants PPT 

Internet4Classrooms - Susan Brooks and Bill Byles have developed an extraordinary web site providing tools and support for you as you integrate technology into your classrooms. Grade level help and literacy projects, some of the best tech lessons I've seen, and they'll answer almost any tech question you have.

Technology Assisting Literacy Knowledge (TALK) - The Fayette County (Kentucky) Public Schools offer a sweet little site full of literacy activities broken down by software application, so you can find what you need based on what you have.

Thinkfinity - Supported by the Verizon Foundation, this is another site with links to thousands of lessons, from the simple to the complex and for all grade levels. Includes stuff for AP classes, and the search utility is really nice...

Edsitement - from the National Endowment for the Humanities, this is another depository of lessons and links. The government really does do some things very well.

4Teachers.org - Quizzes, rubrics, lessons, calendars, and more. Almost everything you need to develop first-rate online tools for your class. And it's free!

Google Earth - If you haven't discovered this bad boy yet, it's time to do it now. Take your students anywhere in the world with a few keystrokes and open their minds. Requires a software download, but it's free. Free is good, and I guarantee your students will love this.

Edutopia - A service of the George Lucas Educational Foundation, this well-designed and well-maintained site offers wide-ranging information, advice, and techniques to aid in understanding and expanding the learning universe for your students. I especially liked the report on low-cost connections to classrooms around the world, Global Education on a Dime.

University of Delaware - One of the foremost authorities on Problem-Based Learning (PBL). Lots of links and resources here to guide you as you engage your students more fully in the educational process. 

North Carolina State University also has a nice summary and description of PBL on their web site. It's a bit outdated - it hasn't been maintained since 2002 - but the information is general enough to still be valuable.

Route 21 - From the Partnership for 21st Century Skills, this is another site full of free resources or links to them. The organization is dedicated to developing the skills your students will need to become productive members of society.

Illinois Math and Science Academy (IMSA®) - Though focused on the college readiness of Illinois high school students, IMSA's mission is "to ignite and nurture creative, ethical scientific minds that advance the human condition". This site has a lot of good theoretical and practical information regarding PBL, as well as links to resources at IMSA and elsewhere. 

ISTE - the International Society for Technology in Education has developed technology standards for students, teachers, and administrators. The National Educational Technology Standards (NETS) provide a sound foundation for digital life in the 21st Century, and this site even provides specific lesson plans and evaluations. Give yourself a lot of time to see everything they have, or join the organization. And no, they didn't pay for that plug. It's just a great organization. 

K12IMC.ORG - Dr. Bonnie Tenenbaum has put together a practical guide to the use of technology with loads of links to valuable information.

Regional Educational Laboratory Program - From the Institute of Education Sciences of the US Department of Education, these ten regional labs provide research and resources to educators at every level, in every subject. One of the better ideas the Federal government has had..

Federal Resources for Educational Excellence - Links to web sites with lots of info regarding lessons, assessments, and more, compliments of the US Department of Education. 

Microsoft Tutorials - Oh my, there are so many free sites devoted to taking you step-by-step through the use of most software. Microsoft, creator of the most commonly used productivity products, provides tutorials to teach you how to use every one of them. I'll find more for you and post them here at a later date.

Hyper About Hyperstudio - Like many other programs, there are lots of web sites devoted to teaching you how to use this powerful product. This one from the Utah Education Network is as good as any.