[I]t really looks to me like there’s a sharp discontinuity between two groups of teachers here. Physical and special education instructors, as well as elementary school teachers, are less intelligent than the average college graduate. The other fields far less so, and in their domain of specialization they seem to be superior to the average college graduate.

That’s Razib Khan, who blogs about genetics at Discover Magazine. (Hat tip: Andrew Sullivan.) Khan crunches more data on the intellectual aptitude among teachers, comparing SAT scores and Praxis test scores, which are used to get teaching certification.