Want to share just a bit of a YouTube video, here's a free online option that allow you to select the pieces you want. Looks helpful. I poked around--fairly easy to use.
CmapTools (free, of course) allow for the developing of concept maps and you can link to images, videos, documents, etc. Not quite as flexible as Inspiration (which is my favorite, but it costs money), but a good option.
Masher is free--can combine digital audio, video, text (yours and Masher's) to produce videos. Kids very muck like mashing--you need to encourage attributions, however.