Northwestern HPME/Brown PLME Suggestions

I’m a high-school junior who is interested in the PLME/HPME programs, and I want to make myself more competitive for these programs in terms of extracurriculars. So far, I have volunteered at hospitals, completed a summer research internship, and participated in competitions such as science bowl/olympiad. What else would you all recommend doing?

Pick what your passionate about and stick with it consistently (multi year) and distinguish your self doing it.