First off, let me start by saying I watch way too much youtube. When I found out about uBlock, I knew I wanted to install it and write a review. I enjoy this app very much. It has taken my youtube watching to whole new level. But that is not the only objective the app has. It stops pop up ads and keeps tracks of how many it intercepts. It gives you some control on pop ups, media elements, cosmetic filtering and remote fonts on sites.
Which could be useful for your classroom. You can’t always control what exactly pops up or some kind of media advertisement on the side that may not be very school appropriate. This may sound like a minor thing, but none the less, helpful while managing the content of what your students see.
It does it job very well, from the reviews I read it does a better job than other ad blockers. But it is one dimensional and maybe that is its weakness. Maybe it could offer some kind of identification of whats being blocked.