(See Alex's Story at http://www.alexneedshelp.com)
This is Alex after getting some marijuana on two different occasions. Note that while he's had a pretty good amount of marijuana, he's actually not simply happy and giggly, but also actually paying attention to what's going on around him. For Alex, this is of critical importance for learning.
Marijuana may have long-term risks about which we know very little - but compared to the long-term risks of severe self-injury and all the meds he's on right now, I think it's a no-brainer which to choose.