Teachers love YouTube. There are a lot of educational videos. To download videos and then show them from your sites (blog, wiki, or your personal website) you can use a DownloadHelper. It is an add on plug in from Firefox. Here is a video that guides you through the steps how to install it on your computer and use it when you want to save a video and add it to your websites. Hit the hyperlinked word DownloadHelper. Enjoy!