Ruiz, usually fairly circumspect in her public comments, said she was not against the system building to 35 percent over time.
"It would be a more responsible approach if we grew to that 35 percent," she said.
Ruiz also said gauges of student achievement for teachers whose pupils are not tested needed clarifying in the regulations. Asked whether she had shared her concerns with state officials as the regulations wound their way through the administrative process, Ruiz said she had and would continue to do so.
"I am going to work very hard to make sure the regulations fulfill the intent of the bill," she said.
The pace of change has been one of the prime concerns about the new regulations since they were introduced last month. The administration does not appear to be bending much, however, as the proposed code goes to the state Board of Education for a second discussion and its first public hearing on Wednesday.
Once through the hearing, the code moves to the formal proposal stage. At that point, it is hard to change without starting the process again. The timeline is tight, with final approval scheduled for fall, when districts are required to have the evaluation systems ready.
State Education Commissioner Christopher Cerf, who worked with Ruiz in crafting the tenure law, said Thursday his staff's regulations were in keeping with the statute that Ruiz sponsored and that was unanimously approved over the summer.
Under the statute, as much as 50 percent of a teacher's evaluation can be determined by state test scores. The state plans to use a measure called "student growth percentiles," in which children's progress is compared against other children with similar achievement levels.
"We took an extremely measured approach to that unanimous statutory mandate," Cerf said.
He also stressed that the measure would apply in the first year to only a fifth of teachers, those teaching children with at least two years of state testing. Those would be language arts and math teachers in grades four to eight.
Still, Cerf said he expected some unspecified amendments to the proposed regulations as they come back before the board. "We are stepping into this slowly over time, and operating well under the ceiling authorized by statute," he said.
The state board is the next stop in the discussion, beginning Wednesday. The board already has some concerns about how particular teachers are to be evaluated, such as those working in special education.
Board president Arcelio Aponte said that although he had not yet heard much feedback personally, he expected more to come, starting with the Wednesday hearing.
"I'm sure we'll have quite a few people there," he said.
Read more of John Mooney's education stories at www.njspotlight.com.