As in most things, education is most important. I am 59 years old and saw my very first case of bipolar disorder about two years ago. I can understand why someone not familiar with this particular condition would be totally confused if and when they see it. Chances are that most all parents and coaches have not seen or recognized someone with bipolar disorder. It is much more severe than just a learning problem. It is a very serious condition that luckily can usually be treated by medication and support.
deebot, My suggestion (FWIW) is to make teachers and coaches not only aware of the situation, but educate them... make copies of medical reports that deal with bipolar disorder. That way, they will not only understand, but will be able to detect potential reoccurences. If they are unwilling to help your son, they deserve what they get when you go to their superiors.