When I was in high school, there was a contest called the Westinghouse science contest. It's one of the biggest science contests in the country and it's since been renamed the Intel science talent search.
Becoming a semi finalist in this contest was a pretty big deal, and becoming a finalist was an even bigger deal, and of course, winning with the hugest deal of all. I entered the contest, but didn't win and did not even make semifinalist.
I know this is going to seem like sour grapes, considering everything, but now that I know a lot about the contest, I think it is all sort of bullshit. I worked in the lab with three other students, and we were each basically randomly assigned projects. Before we started the project or even wrote one word, I could've told you which of the four of us was going to be the semi finalist, based on how interesting the projects sounded.
Don't get me wrong, there were people who came up with math projects that were entirely their own invention, and they were geniuses and definitely deserved to win. But I would say the majority of people who did well just lucked into a really good lab and got assigned an interesting project. For example, I am sure that anyone whose project involved PCR was just following what their mentor told them to do. I know from my own lab, the guy who was a semi finalist didn't do any more work than the rest of us, and basically had no creative say in the project. We all just followed what our mentors told us to do.
I guess this is the fatal flaw in having high school students do fancy science projects.