Do we need to report ehlers-danlos syndrome as a long-term health condition, or does it go away after being treated? My teen is getting ready to go to college.

Yes. If your kid has ED it does not go away. The variable expression of this connective tissue disorder means some are milder than others but the potential for health issues lasts a lifetime. A simple summary of how this disorder has effected your son should help any college health service know at what point to contact you or specialists.
Yes. Both you and your son know how his ehlers-danlos affects him. If it's the severe vascular form that will shorten his life, he's already aware of this and you all have my sympathy. Otherwise, simply mention the likely non-problem -- he's not going to be a football linebacker, and if he gets sudden deep chest pain, knowing he has ed is a tipoff to possible aortic valve tear, which is still rare.
ED connentive tissue. Ed is a connective tissue disease which is genetic in origin. It does not go away and in fact can affect the joints as well as the heart. Both of these systems need to be monitored over the years. Please speak with your primary care provider about more information. I hope this helps.