KANSAS CITY, Mo. - Some states, including Georgia and Alabama, are pushing back against a set of uniform benchmarks for reading, writing and math that have been adopted in most states and are being put in place widely this school year.

The new Common Core standards replace a hodgepodge of educational goals that had varied greatly from state to state. The federal government was not involved in the state-led effort to develop them but has encouraged the project.

While proponents say the new standards will better prepare students, critics worry they'll set a national curriculum for public schools rather than letting states decide what is best for their students. Forty-five states have adopted the standards.

In Georgia, Gov. Nathan Deal signed an executive order in May putting in place restrictions on the standards. Under the order, the state will be prohibited from collecting certain information on students and their families, including religious and political affiliation and voting history. Deal, a Republican, acknowledged in his remarks that the personal information is not now being collected, but said his order was designed to ensure no one's rights are violated.

In Alabama, some Republicans tried without success to repeal the standards. The standards have been opposed by Gov. Robert Bentley and supported by state Superintendent of Education Tommy Bice and a statewide business organization.

There was little dissent nationwide when the standards were adopted in 2010, but that began changing last year and debate picked up steam this year. The standards have divided Republicans, with former Florida Gov. Jeb Bush championing them and Sen. Chuck Grassley, R-Iowa, opposing them.

Lawmakers and governors also are reviewing the standards in Kansas, Missouri, Michigan, Pennsylvania, Indiana, South Carolina and Utah.

Some states are seeking to slow implementation, while others are trying to repeal the standards altogether. Legislation pending in some states would prevent adoption of standards in other subjects, such as social studies or science.

The only states not to adopt the standards are Alaska, Nebraska, Texas and Virginia. Minnesota adopted the reading but not the math standards.

Kristy Campbell, a spokeswoman for the Bush-backed Foundation for Excellence in Education, said conservatives historically have supported higher standards and greater accountability.

"The fact that they are opposed to Common Core now is a little surprising and disappointing given the fact that states came together to solve a need," Campbell said, adding that the new standards will allow for state-by-state comparisons that haven't been possible before. "We are going to have more rigorous assessments that are going to test kids against those higher standards and hopefully achieve what we all want, which is a dramatically greater quality of education in America."

States that adopt the standards are supposed to use them as a base on which to build their curricula and testing, but they can make their benchmarks tougher than Common Core.

While the Thomas B. Fordham Institute, a Washington, D.C.-based research firm, found the new standards to be more rigorous than those that had been used by three-quarters of all states, critics question what will happen in states whose previous standards were tougher.

"So in that regard we really viewed Common Core as the race to the middle, not to the top," said Jamie Gass, director of the Center for School Reform at the Pioneer Institute.

Questions about testing also have arisen. In New York, among the first states to test students based on the standards, some students complained this spring that the Common Core-aligned English exams were too difficult to complete in the allotted time, and there were reports of students crying from stress.

Jonathan Butcher, education director for the Goldwater Institute, based in Phoenix, said opposition also is gaining traction because states and districts are at the point where money has to be appropriated to pay for the standards.

"As soon as states had to start spending money on the Common Core, as soon as it became a line item in the budget, people sit up and take notice," Butcher said. "And that wasn't going to happen until now, until states started to implement it. So it's unfortunate that there is so much attention to it so late in the game but that's kind of where we are. As soon as it starts to become a money issue people will pay attention."