KANSAS CITY, Mo. -- The Missouri Board of Education decided Tuesday to close six St. Louis charter school campuses run by Virginia-based Imagine Schools Inc. because of academic and fiscal management problems.

More than 3,500 students will be affected when the schools close at the end of the academic year, and the state said it would open a transition office to find spots for the displaced students in St. Louis public schools and other charter schools in the city.

"It would be a disservice to the children -- and run counter to the mission of the State Board of Education to ensure a quality public education experience for every child -- to allow the underperforming and poorly managed Imagine Schools to continue to operate," said Missouri Education Commissioner Chris Nicastro in a news release.

Imagine operates 75 charter school campuses in 12 states and the District of Columbia and educates about 40,000 students nationwide.

Jason Bryant, Imagine's executive vice president, called it a "disappointing day" and said the company is exploring its options. He noted the company previously wrote off $4 million in debt from the schools to improve their finances and was making progress in other areas.

But state education officials said in a report that the six Imagine schools spent far more on administration and less on instruction than the typical Missouri school. The report also noted that the schools had difficulty accounting for federal money and might have to refund some of it as a result.

The St. Louis Post-Dispatch newspaper also has highlighted problems at the school, reporting in November that the schools were entangled in complex real estate deals that resulted in high rent payments while classrooms lacked basics such as textbooks. For an earlier story, the paper obtained an email that showed an Imagine official told employees in September 2008 that they should obtain undated letters of resignation from school board members "that can be acted on by us at any time."

In Missouri, charter schools are required to have a sponsor to monitor their performance -- a role that had been filled by Missouri Baptist University until recently. The private university based in the St. Louis suburb of Creve Coeur decided in December to pull the plug on two of the Imagine schools and give the others more time to make improvements. But the state, wanting action taken more quickly, sought to revoke Missouri Baptist's ability to sponsor charter schools. Missouri Baptist didn't fight the effort, agreeing to give oversight of the schools to the state.

The six school closures approved Tuesday include the two initiated by Missouri Baptist. The board also decided Carondelet Leadership Academy, which was overseen by Missouri Baptist but not run by Imagine, will remain open, but with another university sponsoring it.