Great suggestions above for a self-directed amateur project!
But why restrict herself to 'quasi-research' (real research for amateurs) why not professional level research? After 7 years of running a college credit granting, high school science research program associated with a university, I would suggest she do what my students had to do.
Research possible projects to find one that interests her; the traditional amateur crossover projects are a great place to start. Write a short synopsis or proposal of what she wants to research.
Find, through online searches and searches of professional and popular articles/papers, the names and email addresses of professionals working and publishing in that area.
Send an email with her proposed project and ask if the researcher can suggest a college or lab that might work with her on the project, or would be willing to accept her help with an ongoing project already in place. It is also acceptable to call the researchers, but spam calls force many folks to screen nowadays.
I would absolutely include the equipment available to her, given that it is way beyond what folks normally can access.
This takes work on her part (my students were most successful when they sent 100+ emails), but it does sound like she might well be up to the task. Now is a good time to start this, as professors return to their labs and classes start. Late March through May are 'bad' times due to the huge uptick in high school programs sending out this type of email.
I would also have her start with making contact with the AP camp folks, to see where they can refer her.
Whatever she decides to do, if she finds the research intriguing, she will enjoy whatever level at which she is able to participate.