The suit filed Tuesday in federal court in Michigan is the most sweeping challenge yet to President Bush's education policy. It argues that the law is an unfunded mandate, a requirement the federal government imposes without appropriating money to pay for it.
The National Education Association is the lead plaintiff in the action.
Spokesman for the Illinois Education Association, Charles McBarron, says the action is long overdue.
The lawsuit cites a report by the Illinois State Board of Education estimating that developing new tests alone to comply with the federal rule will cost the state $15.4 million a year over the next five years.