Intel ISEF is like the world championship of science fair projects. Its a very cool competition and a wonderful experience. I attended the 2003 ISEF in Portland, Oregon for my project on distributed computing. Hands down the best experience I had in high school.
However, there is a huge disparity between the projects in medicine/biology and everything else. I completed my project entirely on my own with no mentors. Many other CS and engineering projects were similar. The projects in medicine and biology, however, were conducted at a local university under the guidance of faculty and staff, simply because these experiments are not something you can perform at home. They also raked in a disproportionate amount of the awards.
Having switched to biology in college and now working in a lab post-graduation, I've seen the type of work most undergrads and high-schoolers perform. Even if they are intellectually committed, much of the work is actually performed by others in the lab. Undergrads, and especially high-schoolers, often serve as support roles rather than investigators. Obviously this varies to some degree depending on the lab.
My point: Awesome that this student won, and awesome that this is helping to guide her into biology. But, I doubt she did most of the work. Nanoparticle treatment of cancer is not exactly a new idea, so she is likely working under a post-doc who has been working on this for some time.
Looking back at my post, this comes across very curmudgeonly. Perhaps I'm just disappointed that ISEF winners tend to be those helping out professional projects rather than those who design and build the project entirely on their own, or with minimal mentor help.
Edit: to clarify my point, assume a HS student gets out of school at 3pm and work until 5pm, five days a week. That's a lot for a HS student. Unfortunately, 10 hours a week isn't going to get anything done in biology. A single western blot takes longer than 6 hours to run. Hell, I work 50+ hours/week and progress is still very slow.