<p>As an IB kid in a school that offers both IB and AP, I’m tempted to say that the smarter ones choose IB - that’s because, in terms of course difficulty, AP = IB, but you take (at least!) 7 IB classes, whereas most take 2, 3, maybe 4 AP classes, and if you’re going for the full the Diploma, you have CAS and the Extended Essay as well.</p>
<p>So to answer your question - the students who CHOOSE to do the IB are already more intelligent than the norm. Keep in mind that this is anecdotal though.</p>