Hi, I was in HSSP freshman year, and worked as a Peer Advisor for HSSP my sophomore year. I graduated from Michigan with a degree in Cellular and Molecular Biology.
HSSP really just looks for quality essays, and your extracurriculars to see if you have any true interest in medicine/healthcare and community service/volunteering. Check out the link attached below to see what you should write about.
As for high school academics, I met people all across the board in terms of standardized test scores and GPA within HSSP. If you got into Michigan, you’re academically qualified/ good enough to be in HSSP. It certainly doesn’t hurt to have a good GPA, and it’s really low down the list of factors they consider if they consider it at all. I can’t tell you for certain since students in HSSP were never involved in the admissions process. But don’t feel restricted or discouraged from applying to HSSP because of poor grades/SAT scores.
https://lsa.umich.edu/hssp/prospective-students/how-to-apply.html
Pro tip: reading mission statements and understanding what the reader of the applicant is SUPER important for the future when it comes to grad schools/med schools/job applications since you can read the application, know what your audience wants, play to your strengths, and display your commitment/interest in ____ due to past experiences or whatever. It wouldn’t be a bad time to start that with your essay for HSSP. Best of luck!