So interesting! Al Shanker was not its originator but he was an important publicist for the idea, but he renounced charters in 1993 , because (when he saw saw businesses moving into the public school sector,) he realized that his idea had been sabotaged by greed, and turned into a tool with which to bust unions and to privatize public schools . He wrote that charters were no different from vouchers. And he denounced them. ' He did not envision corporate charter chains, nor a charter industry that is 90% non-union, more segregated than district public schools, and inclined to cherrypick the most motivated students.Strangely, neither the right-wingers nor the progressive charter fans ever acknowledge that Shanker denounced what was allegedly his big idea. It is important to recall what Shanker had in mind when he supported charters.' Read this article.