Just playing with Wolfram Demonstration Project. If you want to play, download the free wolfram CDF player to be able to
- Interact with applications from the Wolfram Demonstrations Project
- Explore interactive documents in your web browser
- View Mathematica examples, reports, and files
Eventually, I want to get these interactive demonstrations into my Calculus videos. I don’t think I would be able to do this now. I cannot embed the interactive demonstration into my wordpress.com site, but I could on wordpress.org or any other self-hosted site. I can embed a snapshot, which when clicked, takes you to the interactive demonstration.
For now, I’ve just been playing around with the premade demonstrations they have. I wasn’t expecting such a huge library. I can definitely use some of these in my class next year. I’m always looking for interactive applets. Good visuals are important!
techieMusings 
I’ve always thought that there must be some applications for Wolfram Alpha in the classroom. Not being a math teacher I haven’t had an opportunity to try it out myself.