I decided to try doing animations with my second graders this year and was very pleased with the results overall and truly amazed with the artwork of some of these seven year olds!
I began by showing the students the Brain Pop video about traditional animations. This is a site to which my district subscribes, but a free trial is available.
I demonstrated a simple animation on ABCya and discussed some ideas with the students. I liked the way this site allows you to create a background image. It was important to remind the children to use the background tab on the right to draw things that they wanted to appear in every frame but did not want to move. Although there are 40 possible frames, most of the children only used four or five. A few kids really didn't get the concept and drew totally unrelated pictures in each frame. Many children did very simple animations such as a bouncing ball. The animations can be saved as an animated .gif file.
Here is an outstanding example: