Which are the biggest private companies in the education market in the U.S., Europe, and the world?
I believe the single biggest private education company is Education First (EF – http://www.ef.com/) which is a conglomerate based in Lucerne Switzerland owned by the Hult family. They have a diverse range of education businesses all over the world including language schools, high schools, a business school, and EnglishTown, a large player in online english training.