I have written a few times about the intervention possibilities of YouTube, though I know some cannot access it within your schools (see that link for workarounds). Google is surely in the process of making their own YouTube app for iPad (there is already one for iPhone/iPod that you can install, but it will be small-sized/resolution-challenged). In the meantime, however, check out Jasmine, a nice, elegant, timely YouTube client that works exactly as you would expect it to work:
Keep in mind that when downloading Jasmine, you will receive an "age-restricted material" warning. YouTube certainly can be racy, so don't ever allow kids to search for what they would like to watch, obviously.
Common Core Connection:
CCSS.ELA-Literacy.SL.5.2 Summarize a written text read aloud or information presented in diverse media and formats, including visually, quantitatively, and orally.