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The IB itself is recognized by American universities as an excellent preparation for college, and even the tippy top universities award 1-2 semesters’ worth of transfer credit for it. So that won’t be an obstacle.</p>
<p>On the other hand, attending a high school in the US might give you way more opportunities to “stand out” than most foreign school systems. For example, American students can pretty easily compete in all sorts of competitions or work on projects that other people have organized. A strong performance will show that you are a star student on a bigger scale than your local high school graduating class. When a foreign school system and culture does not offer these opportunities, it might take a <em>lot</em> more initiative to build a resume that appeals to the top universities.</p>