I have created a small web page what you can use for practice, with a two color glass (3D glass) you can try to use your eyes together.
This is just an extremely small web page (and not finished yet completely) but you can find it useful maybe
give it a try if you think
(but if you have vision problems you can find this very hard or extremely hard to read much more harder than the Tetris game):
You can find this here: Lazy Eye Reader
It is works similar to the following vision therapy tools:
Lazy Eye Tetris 