A contribution from Diane Ravitch:
Once in a while, someone complains about the fact that the Department of Education has its headquarters in the Tweed Courthouse, next to City Hall. This is really unfair, as you will see. Most people make the connection between the Tweed Courthouse and Boss William M. Tweed, the corrupt head of Tammany Hall. What they don't realize is that Boss Tweed served as a member of the elected New York City Board of Education from 1855 to 1857.
As his power grew, he decided that the Board of Education was a rich source of patronage. In 1869, Boss Tweed persuaded the state legislature to dismiss the elected Board of Education and replace it with an interim board that was appointed by the Tammany Mayor. Friends of Tammany cried that the independent Board was extravagant, spendthrift, etc. One of the first acts of the Tammany-appointed Board of Education was to measure classrooms and figure out how to squeeze more children into the same space.
In 1871, with Boss Tweed riding high, he amended the City Charter to change the Board of Education into the Department of Public Instruction. The legislature supported the change, and for two years--until the Tweed Ring was exposed--the public schools were operated by the Department of Public Instruction. Except for The New York Times, the other newspapers in the city commended the change, saying that it would bring the schools into a closer relationship with municipal government and would streamline their administration.
Once the Tweed Ring scandal broke, the legislature abolished the Department of Public Instruction and restored an independent Board of Education.
Anyone who wants to read further about the adventures of the Tweed Ring will find this account in more detail in my book "The Great School Wars, 1805-1973," pp. 92-99.