Some excerpts from an article about a school district in Denver:
http://www.denverpost.com/news/ci_11280071

Quote
Adams 50 will eliminate grade levels and instead group students based on what they know, allowing them to advance to the next level after they have proved proficiency....

Students will be tested this spring to determine their proficiency in reading, writing and math, and will be grouped next year with peers who are learning at the same level...

"This is a departure from one-size-fits-all," said state Deputy Education Commissioner Ken Turner. "It's more customized learning. If we want a path to better results, we should be willing to try different things. . . . We applaud their efforts..."

Van Schoales, education expert at the Denver-based Piton Foundation, is skeptical about Adams 50's chances.

"There is a reason why school districts have a hard time implementing this, because they don't replace their old systems," said Schoales, who added that his only understanding of Adams 50's plan is from its website.

"It is like adding a new program on top of an outdated, old computer with a poor operating system," he said. "To create this new system on top of this existing system that is time-based is probably not going to work."