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AUSTIN (CBSDFW.COM/AP) - Outgoing Texas Education Commissioner Michael Williams has urged the Board of Education to keep state testing and academic accountability standards high.

In his last address to the board Wednesday, Williams said, "I encourage us to maintain a rigorous assessment system."

He added that he'd like to see Texas "maintain an accountability regime that makes sure that high performers are rewarded and low performers are recognized."

Amid an outcry about possible over-testing, the Republican-controlled Legislature voted in 2013 to cut the number of standardized tests high school students must pass to graduate from a nation-high 15 to five.

Beginning next year, meanwhile, the state's academic rating scale measuring public-school performance begins the controversial practice of issuing letter grades A to F.

The top education official in Texas plans to step down after the end of the year. According to a letter, Williams says he wants to spend more time with his wife at their home in Arlington, which is about 200 miles away from the capital.

Williams was the first African American to be named the state's education commissioner.

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