The Washington state Senate has approved a series of K-12 education reform bills meant to strengthen schools and improve learning.

The measures passed by the chamber Wednesday are in large part the fruit of a Republican takeover, together with two Democrats, of the state Senate.

"We're challenging the status quo," said Sen. Bruce Dammeier, R-Puyallup. "We're looking to in some cases do what I might call disruptive change."

Among the bills passed is one to give veto power to principals over teachers assigned to their schools. Under that bill, teachers without a school assignment could be deployed as substitutes or used in non-teaching roles and could eventually be fired.

Another bill would set up an A through F grade scale for K-12 schools. The grading system would be set up as a pilot program in a handful of schools starting in the fall of 2013. After an evaluation, it would be implemented statewide the following year.