I am far from being a specialist. However, I had the chance to work with students that were dealing with mental troubles. The first thing that I had to understand is that most of the kids already loved me. It was my duty to love them. This was quite unusual since most of the teenagers don't really appreciate their teacher at the beginning. You also have to be ready to be patient. They don't all go to the same rhythm. Every discease is different, so all the students have different needs. Take the time to personnaly know each of them; it is also a security issue. Games are really important, it is surely the best way to make them learn. Please know that there are tons of websites dedicated to this subject. Take the time to get advices from experts. Good luck!