The new coins will be minted and issued in 10-week intervals throughout 2008 with designs honoring Oklahoma, New Mexico, Arizona, Alaska and Hawaii. These coins wrap up the series that began in 1999 with a quarter honoring Delaware. Surveys by the Mint have found that nearly half of all Americans collect the state quarters, either in casual accumulations or as a serious numismatic pursuit.

The director of the Mint, Edmund C. Moy, called the series a "remarkable success."

"They have educated a whole generation on geography and history," Mr. Moy said.