
First off, a caveat: I'm not a lawyer and I don't play one on TV. For legal advice, always consult your attorney. All right, moving on. From my reading, it appears that this applies to programming that has been shown on television and does not apply to "web-only" content. If you are producing content in your home studio or school media center, this law does not legally require you to add Closed Captioned content to your video projects that you upload and show online. That's my take on it, anyway.
However, this does not answer if you should provide CC or subtitles on your video projects. Does it serve your audience to have this content available to the hearing impaired? Is it a good idea even if it's not legally required? That is something you need to consider with your current and future video projects.