I wouldn't focus on the negatives the whole time, but I would definitely address them briefly. Kids need to know what they are getting into. I think it would be the duty of a speaker in a situation like that to give an accurate portrayal of the job. There are pros of flying that you can talk about too, and some kids will probably love the pros of flying.
It would not be fair to go in the school and do nothing but fluff the job up and act like it has no cons. That would honestly be worse for the kids on the long run than to present both the pros and the cons. Plus, if a kid REALLY likes flying, and wants to fly, they will probably fly anyways. I have been discouraged my whole life from old pilots about how I shouldn't fly. Honestly, they made me really second guess it a few months, but I came to the realization that I would NEVER forgive myself if I at least didn't give the profession a shot. I really did not want to live with the "what ifs" about if I had tried to pursue the dream and fly. I went to school and got a degree non aviation related that I can utilize if flying doesn't work out. I would suggest telling high school kids that getting a degree in something besides aviation is definitely something they should consider. Don't tell they they CANT get an aviation degree, but definitely let then know that getting a non aviation degree is a viable option, and one that may lead to a little more flexibility down the road if they see that their life is suffering big time because of flying and they need to get out.
TLDR: Tell them both sides of job, the daily activities of the job, and ways to get there. You aren't selling aviation jobs to these kids, you are teaching them about being a professional aviator.
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