Given the problems already discovered with Common Core math problems, it is not surprising that states are now reeling over cost calculations related to its implementation.

Some are now reconsidering their participation.

States are learning the cost of Common Core is uncommonly high.

The federally-backed standards initiative, first proposed by the nation’s governors and an educators’ association, seeks to impose a national standard for achievement among K-12 students. So far, 45 states plus the District of Columbia have signed on, with some implementing curriculum designed for the Common Core Standards Initiative during the current school year and the rest set to take part in the next school year. But several states are reconsidering their participation, and one big reason is the cost.

States will spend up to an estimated $10 billion up front, then as much as $800 million per year for the first seven years that the controversial program is up and running. Much of the cost is on new, Common Core-aligned textbooks and curriculum, but the added expenses also include teacher training, technology upgrades, testing and assessment. The figures are taking states by surprise.

“It’s a fair amount of money given a lot of states signed up without any cost analysis,” Theodor Rebarber, CEO and founder of the nonprofit Accountability Works, which sanctioned the study on the projected costs of Common Core, told FoxNews.com. “Just looking at the cost aspect, it was not focused at the time, so a lot of jurisdictions did not realize what would occur down the road.”

A 2012 study by the Thomas B. Fordham Institute called, “Putting a Price Tag on the Common Core: How Much Will Smart Implementation Cost?” found the costs for implementing Common Core will vary, depending on how much a state buys in. The study detailed three levels of implementation – a “Bare Bones” rollout plan, a “Business as Usual” traditional plan (the priciest) and a hybrid, or “Balanced Implementation,” combining the most and least expensive elements.

Education officials in Maryland estimated in a report last month that it will require $100 million to upgrade computers statewide to support the testing that is the centerpiece of Common Core. Georgia and California are also finding that costs are too high to implement Common Core, with the latter estimated to spend approximately $35 million per year, or about $30 per student, in testing costs alone.

The study by Accountability Works, the Maryland-based nonprofit education advocacy group, estimated that schools nationwide will need $6.87 billion for technology, $5.26 billion for professional development, $2.47 billion for textbooks and $1.24 billion for assessment testing over the first seven years that Common Core is in effect.