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The College is the upgrade to the Schoolhouse, producing double the education points! Assigning a Free Colonist, Indentured Servant, Converted Native, or Petty Criminal to the Student profession here will allow them to adopt the specialization of any Specialist unit in your settlement more quickly than with a mere Schoolhouse.
A college is an institution of higher learning, although the exact meaning of the word differs greatly based on the culture which is using it. In the English system of education, colleges are often specialized institutions that make up a university. Oxford University, England's most prestigious university, had 17 individual colleges by 1610. The English college system would be adopted by her colonies in the New World, and by 1636, North America had its first college, Harvard College, which, with time and investment, grew to become the world's most renowned university.