"Animoto is an excellent tool for creating audio slideshows. But there are some limitations to it that some teachers don't like. Most notable of those limitations is the time limit (30 seconds unless you get an Animoto for Education account), lack of space for text, and that students have to remember a username and password to use it. The YouTube slideshow tool provides a tool for creating audio slideshows without those three limitations of Animoto."
This page shows how to use YouTube for slideshows so that they are longer and more accessible to students that other sites like Animoto. I had no idea that YouTube had this capability. In my district, YouTube is blocked on campus computers (I'm sure many others can sympathize) so I would need to work around that if I had students using this in a lesson. Recently I began to use SlideRocket to create video lessons so that I can incorporate audio narration and the link is not blocked by the district's web filter. SlideRocket could be used for a slideshow as well, but it takes a lot more customizing than this YouTube method. This blog has a ton of other useful information too. Kudos to the writer!