State-level battles over changes in education policy have shifted in many places from legislative chambers to courthouses, as unions and other critics of new laws challenge them on the grounds that they violate state constitutions and worker contracts. Republican governors and lawmakers--their ranks bolstered by the 2010 elections--won passage this year of ambitious measures in many states that often drew strong opposition from teachers' unions. Points of dispute include changes in how teachers are evaluated and compensated and expansions of private school vouchers. The strategy of challenging such laws in court, while not new, comes as GOP elected officials pursue agendas loaded with policies reviled by many unions. In addition to legal actions challenging voucher programs, lawsuits filed in Florida and New Jersey seek to block the adoption of new laws that require teachers and other public employees to contribute more toward their pensions. A second suit in Florida attempts to block a new, far-reaching law that phases out tenure and implements merit pay for teachers. A legal action in Idaho takes aim at a similar law that phases out tenure and ties teacher evaluation to student performance.