I agree that teens need to shower. My son is 15 and takes two showers a day. One in the morning and one after school (he takes weight lifting). I never had to say anything either. Maryland can have some high humidity.
Maryland is beautiful. My brother-in-law lived in Greenbelt. My favorite was Ocean City. And of course, there is DC, Antietam, etc.
But I remember it being very humid. I almost got heatstroke because I wasn't used to the humidity — I spent most of the *running* around Gettysburg. The locals would probably tell you this is foolish, even if you are acclimated.
Remember it rained when we returned to Greenbelt — here in Colorado, a rain can drop the temperature by 20 degrees or more. In Maryland, the temperature stayed the same (really hot); it just got more humid.