Arizona has more than doubled the number of teachers who have national-board certification in the past five years.

The newest batch of nationally certified teachers in the state totals 107, according to the National Board for Professional teaching Standards

That's according to the Arizona K12 Center, a non-profit agency that helps teachers in the voluntary but rigorous national-board certification process.

The Arizona Republic says 957 teachers in the state have earned the certification overall. That's more than double the 461 teachers total certified in 2006-07.

The districts with the most newly certified teachers are the Tucson Unified School District with 15 and the Scottsdale Unified School District with 13, although one of those has retired.

Gilbert Public Schools has the most overall with 105, including one newly certified teacher.

Information for how Arizona teachers can work toward the certification process is on the national board website, www.nbpts.org.