PresentationTube Recorder is a tool designed to record Ppts for 15 minutes--free, of course, though there is a paid version that allow more to be done. Worth a look
You can turn a doc, PPt and more into an interactive book. I see lots of potential here if you write books with students that are then shared with families. Free, of course!
Free version allows 15 minutes (10 PPts narrated and turned into videos/month)...some adds, however, and no animation. Great potential for student presentations