Has anyone encountered/heard someone that looked smart then when they open their mouth they weren't?

There were some girls I went to high school with. They received good grades and were very high maintenance and materialistic. They were 'preppy' per say. They looked smart, but didn't wear glasses. You'd assume they were smart because of the grades.

If you talked to the girls, they did not sound smart. They only learned thigns that were for tests to get into a good college. I doubt if you asked them anything about physics, they'd remember. Ask them about Black Holes and they probably would not have an answer. They are not real intellectuals because they don't do any outside research for fun.

Their actions also show they aren't very rational, either.