They don't really exist.  See a recent thread started by DeeDee.  I've also called the admissions office at my alma mater figuring they'd have seen a significant number of examples of people with similar problems, and they were clear - they interpret online science at the high school level as the student knowing a low level of the content, but generally without a quality experience in intellectual engagement.  They recommend JC classes, intense summer experiences through gifted centers, or an informal research experience with a practicing scientist.