I experimented with Animoto and Stupeflix. I created a video using the same set of pictures so I could compare the two programs and see which one was easier to use and which one would be more effectively used in my classes. I uploaded a series of photos I use in Photo J when teaching students about the importance of capturing emotion in their photos. I def. like Stupeflix better, but it is pricier. The free version allowed a much longer video, but you only get one free video, I think. Animoto has unlimited free videos, but they are only 30 seconds long. I REALLY liked that I could upload to Stupeflix directly from Dropbox, which I did. That worked very well. Here is my Animoto video.
Make your own photo slideshow at Animoto.
Here is my Stupeflix video: