Speaking at a charter school his wife helped found, U.S. Rep. Bill Cassidy called Monday on his opponent in the U.S. Senate campaign to renounce a lawsuit filed by a teachers’ union that endorsed her.

The purpose of the lawsuit is to strangle some charter schools’ funding and force them to close, said Cassidy, who is the leading challenger to the re-election of Democrat Mary Landrieu in the Nov. 4 balloting. Landrieu was endorsed by the Louisiana Association of Educators, one of two teacher unions in the state, which last week filed a lawsuit challenging the constitutionality of the public money — about $60 million — being used to fund specific types of charter schools.

The lawsuit could tie up charter schools’ funding long enough to force them to close, Cassidy said, surrounded by about 20 dyslexic youngsters and standing in front of photos of Albert Einstein and John F. Kennedy, both of whom had the common reading disorder.

His wife, Dr. Laura Cassidy, helped organize the school that teaches dyslexic students to understand written letters and serves as chairman of its board. One of their daughters is dyslexic.

One of every five people in the nation has the processing disorder that jumbles up letters and makes reading difficult, Cassidy said.

Training youngsters to encode correctly costs $10,000 to $50,000, making it very difficult for many parents to afford. “Parents deserve the right to choose,” he said.

The Louisiana Association of Educators filed a lawsuit last week that argues the state constitution allows funding to flow only through “parish and city school systems.” The state Board of Elementary and Secondary Education authorized some of the charter schools that get aid through the Minimum Foundation Program, which the LAE says was unconstitutional.

The lawsuit, if successful, would strip money from the schools’ MFP, which is a complex formula that establishes how much of the $3.6 billion in state taxpayers’ money each public school receives.

The Louisiana Key Academy is on the list, as are Louisiana Connections Academy and Louisiana Virtual Charter Academy, all in Baton Rouge, and International School of Louisiana, Lycee Francais de la Nouvelle Orleans and the MAX Charter School, all in New Orleans.

“If we lose our MFP, we can’t have the school,” Laura Cassidy said. “I want our elected leaders to be in favor of charter schools. This shouldn’t be an issue.”

Cassidy said her school, which has 181 students, had a lot of specially trained teachers because dyslexics need to work in smaller classes. The academy also integrates its training to help students recognize letters into its math, social studies and other courses as well.

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