Eye patches have apparently been tried over a decade ago with some success -- here's a reference from around 2000:
http://www.independent.ie/irish-news/eye-patch-therapy-a-boo...
The difference is now we have a strong hint as to why they work.
I would expect that the social stigma would severely limit uptake in school though, which is why this isn't standard today -- kids can be rather vicious when they pick up on any hint of difference or weakness.