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<li><p>Well, I think it’s important. Physics isn’t all about math. But building up an intuitive understanding physics takes time and can be done alongside learning all of the math. I don’t really know what else to say about this!</p></li>
<li><p>I don’t even know what you’re talking about. Usually, college admissions people care about what you did in high school but once you’re accepted nobody cares. When you are applying to grad school, grad school admissions people will care only about what you did as an undergrad (you may as well be a high-school drop-out that got their GED as far as they are concerned), but once you’re in grad school nobody will care. When applying for post-docs, people care primarily about what you did in grad school and maybe what you did as an undergrad (if it stands out in some way like some publications or your undergrad school has an impressive name like MIT) but your grad school work is far more important. I can’t imagine anybody caring about what you did in high school by the time you apply for tenure track positions (if tenure track positions still exist by that time).</p></li>
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<p>If, as you say, you’re already accepted Cornell, then your high school experiences (unless you flunk out) officially don’t matter to anyone anymore, congrats!</p>