As for the education of the American actresses,

Natalie is not alone. Though it is rare, there have been some well educated actresses around. Brook Shields graduated from Princeton, Judie Foster Yale. There are a couple from Stanford too, whose name I can't recall at this moment.

Only that they in general can't compete with those high school graduates in the film industry. One of the reasons probably is that the film industry demands high profile, which a really content person might not be very comfortable to follow.