"PIP before used to mean you're in big trouble, and now it may be 'here are some weaknesses and how you can get better,'" said Emily Cohen, policy analyst for the National Council on Teacher Quality, a nonpartisan group that supported the contract. "I think it shows a real effort on the part of the district to make evaluations better and help people do better."
Cohen said that for the district's strategy to be effective, it must change the culture and thinking behind what is often considered a means to termination.
"This effort all falls on how well the district is able to communicate with teachers," she said.
Other experts said city educators are right to worry, given the national discourse about holding teachers accountable for public education failures.
"I think that what's happening in Baltimore is symptomatic of a national rush to judgment," said Diane Ravitch, research professor of education at New York University and historian of education.
Ravitch, who denounces using student test scores to rate teachers as "insane social policy," said that soon teachers across the nation will be shuffled around as districts look to evaluate them out of the classroom.
"By design, someone in the system has decided that there are a certain number of teachers who should be on their way out the door," Ravitch added. "This is huge. You have a school system that has designed a method to demoralize virtually every teacher in the school system."
At the beginning of the school year, city schools CEO Andrés Alonso told principals that they need to be more stringent in evaluations. He said it was impractical that during the 2010-2011 school year, 108 of the city's roughly 200 schools had no teachers rated unsatisfactory.
Of the city's 6,900 teachers, about 4,400 — or 63 percent of the teaching force — received proficient evaluations at the end of last school year, and about 2,200 teachers were rated satisfactory. About 200 teachers received an unsatisfactory rating at the end of the year.
Michelle Rhee, the former chancellor of Washington, D.C., public schools who founded StudentsFirst, an organization that has lobbied for radically reforming public education, said the disconnect between student achievement and teacher evaluations is prevalent throughout the nation.
"We have a system in this country where the vast majority of teachers were being rated as effective, and the student achievement levels on assessments were not reflecting that," Rhee said.
She gave the example of Washington, where at the beginning of her tenure, eighth-graders were posting 8 percent proficiency levels but nearly 98 percent of teachers were rated effective.
Rhee said that not only is it "extraordinarily difficult" to fire poor teachers, but schools could use a radical turnover to replace weak teachers.
"That is the kind of movement that we would want to see in a system, that is not only completely acceptable, but that we should as parents, as a country, want to see," Rhee said.
The Baltimore Teachers Union said in a statement that it was still investigating how large the increase in improvement plans is. The union also said that the district's approach "is not a good way to develop school leaders and not fair to teachers."
The union can grieve the process of a PIP. But that doesn't apply if a principal can document providing support to a teacher, and the teacher hasn't improved.
School officials said that before this year, that process was never documented, and that moving forward, PIPs will represent a contractual agreement between teachers and principals.
Last month, teachers across the city received an email informing them that their appraisals were ready.
Some teachers told The Baltimore Sun they received the first unsatisfactory ratings of their tenures, some spanning decades, resulting in a PIP. Others said that while they aren't on PIPs, they were downgraded from proficient to satisfactory for the first time in many categories, and fear it will be harder to receive an overall proficient rating for the school year.
In the past, teachers said, the midyear evaluation involved an intense conversation in which they were given an opportunity to present evidence to challenge their evaluations. This year, it involved clicking a button in a new online system to accept whatever ratings they received.
One English teacher who has taught in the city for more than a decade said she was given an unsatisfactory evaluation for the first time and was placed on a PIP.
"When it comes to the end of the year, they can try and not renew me because of this," said the teacher, who spoke to The Sun on condition of anonymity because she fears retribution. "I try to just put it aside because I still have to go in there every day and serve the kids the best that I can."
The focus on teacher quality has also caught the attention of parents.
Melanie Hood-Wilson, the teaching and learning representative on the Parent Community Advisory Board, said the board believes that "there needs to be a mechanism for getting substandard teachers to leave the classroom, but we also want to make sure the supports are there to keep the good teachers and help the good teachers improve."
Kirsch, the Educators for Democratic Schools spokeswoman, said the group is rallying educators around the city to protest the district's new approach to PIPs. At one high school, she said, teachers who have been put on PIPs have sent uniform responses to their principals that say "this is illegitimate and untrue."
"The next step is to get these wiped off and actually have some conversations," she said. "We want people to stand together and say that this is not the Baltimore that we're going to teach in."