Big difference between public and private schools. Getting expelled from a public school is pretty hard, you basically have to do something seriously illegal involving guns and/or drugs. Getting expelled from a private school is an entirely different thing. They can expel you for a lot of things, and basically anything that makes the school look bad in the eyes of prospective future 'customers' is high on that list. Especially among more prestigious schools.
I don't know, my anecdotes would be from a private school in Europe where a family member is a teacher. They take plagiarism seriously, but also can expel students a lot easier than public schools can.
The point being is that plagiarism at a known private school that you pay good money for and hope to rely on, is something you will give much more consideration than sending work to a science fair to see if it will stick to a wall or not.
Neither are particularly good behaviors, but as a "computer guy" I think your public-facing API (science fair admissions) should validate its inputs. There are people out there who send know malicious requests to endpoints, you know.
Instead of blaming an underage student I'd reevaluate all of their prior nominations. Chances of dragons being there.
I totally agree that the fair failed badly at validating the submissions.
> The child is nothing to be blamed for, it is a 100% problem of the organizers.
This is what I disagree with. A 17 year old is not an innocent child that mustn't be blamed. At this age (and already earlier too) there has to be real consequences for plagiarism, proportionate to the case.
Plagiarize coursework? Fail the course. Cheat in final exams? Fail the exams and retake the year. And so on.
So let him fail the science fair and probably be banned from entering this science fair and probably other ones if they're federated.
If that's not his first participation then the previous ones should also be reevaluated.
But that doesn't have much point since he's growing out of them already. And I don't think it's fair to pursue him further (other than existing bad publicity) since people do stupid things all the time and the idea of limited liability exists for a reason.
I'd see some evidence.