After New York City spent years building a thriving charter school community, Bill Phillips, president of Northeast Charter Schools Network, says Mayor Bill de Blasio is showing how to take it down.

"If New York City has been a national model for growing charters, I think Mayor de Blasio is laying out a blueprint for killing charter expansion," said Phillips, whose school network serves New York and Connecticut. "This is clearly a blueprint: Do everything on your power to take away access to buildings. Facilities are almost always one of the major challenges for charters across the country."

In New York City, 70,000 students attend charter schools and more than 50,000 are on waiting lists.

During his campaign, de Blasio clearly voiced his intention to charge rent to charter schools co-locating with district schools, sparking a protest involving about 20,000 charter school supporters.

Between the high cost of New York City real estate and a desire to keep actual school sizes relatively small, it's common for districts to run multiple schools out of the same building. About 10 percent of co-locating schools are charters, Phillips said.

About three-quarters of New York City's charter school students attend co-locating schools.

Last week, de Blasio's administration pulled $210 million allotted for new charter school buildings and directed it to expanding preschool programs. He's placed a moratorium on new charter school co-locations. And schools slated to open soon with co-locations approved by former Mayor Michael Bloomberg may see that approval taken away.

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