<p>Assuming that you are a junior and will apply next year...</p>
<p>For MIT and Caltech:</p>
<p>You will be a very competative applicant no matter. SATs, GPA, and 'regular' ECs can't make anyone a sure accept, but you're definitely in the running. </p>
<p>If you do make USAMO, you increase your chances dramatically. Of course if you medal internationally, that's a sure way to get in (I'd imagine...), but even just going would be a huge boost to your application.</p>
<p>Research is another great way to put yourself beyond most competative applicants, and if your research goes well/is interesting, I would be surprised if you didn't get accepted.</p>
<p>Your GPA is one what scale? 3.91/4.00?</p>