One way to add animation to your lessons/website is to learn Flash. I know how to do this… I choose not to because (a) it is time consuming and (b) all my students have iPads.
In the past I have used animation-ish to create animations and export as Flash. Much easier than creating the animation myself in Flash. I would upload an image of an xy axis and then animate the process for graphing the slope of a line. A nice little graphic to include in my Moodle lesson on graphing slopes. I like how unlike a video, it plays automatically and loops.
However with iPads, what do I do now? I created the above wiggle cartoon in animation-ish and exported the image files instead of exporting to flash. I then uploaded the files to http://picasion.com/ which created an animated GIF from my images lickety split. You can see it embedded easily into my wordpress blog.
Since most people do not have animation-ish, I made a Keynote (or PowerPoint) with 3 slides and exported the file as images. I uploaded the 3 images to the http://picasion.com/ website and it gave me an embed code I could easily insert here.
For Keynote go to the File Menu and go down to Export. One of the export options is to export as images. Note, I also use this method to create backgrounds for iMovie.