<p>I agree with the above. If you are talking about undergraduate students, a college which has 3 Americans has a lot! But there are about 800 American graduate students. They are a lot more common. There are also a lot of American students studying abroad on some kind of 1 term or 1 year programme, but the majority of them have little actual contact with the directly enrolled students.</p>
<p>You’re not going to wander around and bump into students in the summer though. They are all on vacation. You will see US students on summer schools (the university takes their money, they stay in university accommodation and have no other contact with the university but go home and say they studied at Cambridge. What they mean is, they could pay to stay there). </p>
<p>If you want you child to attend a foreign university but not to associate with any non-Americans (I can’t tell from your question if this is the case), it seems that many manage this at St Andrews But I really think this is missing the point of studying abroad.</p>
<p>I bet Trinity has the largest number of medical students, but only because it is the largest college. There isn’t a specialist medical college. colleges are more like dorms, but some teaching takes place there. Lecture are central so all medical students from all colleges would attend the same lectures.</p>