NASHVILLE (AP) — A judge on Wednesday refused to issue a temporary injunction that would allow a troubled virtual school to remain open.

The ruling by Senior Judge Ben Cantrell is the latest setback for the Tennessee Virtual Academy, a contentious online school that has been ordered to close because of poor academic scores.

The families of three children who attend the school filed a lawsuit last month saying Education Commissioner Candice McQueen exceeded her authority when she ordered the school shut down at the end of this academic year. They had argued that their children have special needs — including one who is severely disabled and is too medically fragile to attend a traditional brick-and-mortar school — and are doing well at the school.

"I'm very disappointed for my clients," said the families' attorney, Tara Swafford. She said they are considering asking for an expedited appeal.

The families say if the school shuts down, their kids would be forced to attend failing schools in their community.

The school allows students to stay home and do schoolwork on their computers. The virtual school is run by the Union County School system, but students from anywhere in the state can enroll. Union County contracts with Virginia-based corporation K12 Inc. to provide the curriculum to the students.

Critics of the virtual school have called it a failure and a drain on taxpayer money.

Former Education Commissioner Kevin Huffman last year ordered the school shut down after it had ranked among the worst-performing in the state in terms of academic gains since it opened in 2011. Commissioner McQueen stood by that decision.

The families had argued that the law actually gives the school more time to turn around, and that it was improving.

"The court finds that there is a heavy burden for the plaintiffs to carry in order to succeed on the merits of this case," Cantrell wrote.

Students, the judge said, don't have a constitutionally protected right to go to any particular school. Second, Cantrell said, it is sharply disputed whether the education commissioner violated the law.

As far as the children's special needs, Cantrell said federal law requires states to provide a free public education to all children with disabilities, and that would include giving them an individualized program that uniquely suits their needs.