I am a huge fan of Animoto (www.animoto.com)! This easy-to-use software makes videos look very professional with little effort. To create a video just upload pictures, pick a song and style, and the software does all of the work for you. Although Animoto has been around for awhile, they continually upgrade and change the software, adding more features and options.
Creating an account is free, but you only get 30 second long videos. As an educator, you can apply for a free educator account at www.animoto.com/education.
Here is a video I made using Animoto to promote my mom's new children's book series: