It’s a conversation I have way too often. Someone will think that just because they go to a competitive high school, that this will allow them to have lower grades than students from weaker high schools. And it just isn’t true.
Colleges do consider the quality of your high school. But the most selective colleges are getting students with good grades who also attend very competitive high schools. And colleges are not necessarily going to hold it against you because you happened to go to a weaker high school. Whether a strong high school or weak, it’s all about the grades.
This problem can be particularly acute with BS/MD programs because so many use GPA as a criteria to see if you can even apply to the program. Going to a strong high school and getting a lower GPA does you no good if you don’t even get considered by the BS/MD program.
So does that mean that you shouldn’t go to a competitive high school? No. What it means is that you need to give some thought on which high school to attend if you have choices. The strongest candidate will go to a competitive high school and get good grades. For BS/MD programs, and most highly selective colleges, that means you want to be in at least the top 10% of the class.
If you don’t think you can do that at the competitive high school, then going to a less competitive high school, and doing well there, may be a better option.