DENVER – Nearly four dozen tenured Denver Public Schools teachers are expected to lose their non-probationary status as a result of education reforms passed in 2010.

In Douglas County schools, it’s 24 teachers. The Aurora district expects 12 teachers to lose tenure, Chalkbeat reports.

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Colorado’s teacher effectiveness law requires all teachers to be evaluated every year and half of the evaluation must be based on student academic growth. Tenured teachers who receive two consecutive years of low ratings automatically lose tenure, and new teachers with three consecutive years of positive ratings receive tenure protections, under the law.

The new system is designed to better weed out poor performing educators and improve instruction for students. Before the new system took effect in the 2014-15 school year, tenured teachers were only required to be reviewed every three years, and the review did not incorporate student performance.

Under the old system, virtually all teachers were granted tenure after three years of employment, and very few lost their tenure status, regardless of how well their students learned.

Teacher ratings from the 2014-15 and 2015-16 school year are now being used to determine tenure status, and it’s resulting in more tenured teachers who could lose the job protections.

According to Chalkbeat:

Job security is the biggest difference between probationary and non-probationary status. Probationary teachers are hired on one-year contracts. A district can get rid of a probationary teacher at the end of that contract for any reason allowed by law.

Non-probationary teachers can only be fired if a district can prove one of several grounds, such as that a teacher was insubordinate or immoral. Those teachers can appeal a dismissal all the way up to the state Supreme Court, which can take many months.

A total of 47 teachers in Denver Public Schools set to lose tenure represent about 2 percent of tenured teachers in the state’s largest school district. Other districts are reporting roughly one percent of tenured teachers in the same situation.

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DPS executive director of talent management Sarah Almy told the news site she doesn’t believe the district’s higher rate of tenured teachers set to lose their protections is a bad sign.

“I don’t think this reflects that Denver has fewer effective teachers or that our teachers and what they’re doing to advance student learning is any less powerful or effective,” she said, noting that DPS uses its own evaluation system, rather than a model system promoted by the state.

“And a really important part of that is giving honest feedback to teachers, in both what they’re doing really well and what they need to grow and develop in,” she said.

Others, like National Council on Teacher Quality president Kate Walsh, pointed out that while many states incorporated tougher teacher evaluations as part of President Obama’s Race to the Top education initiative, but “many of the first rollouts of these new evaluation systems have not been impressive in terms of distinguishing between teacher talent.

“Everyone is still getting great marks,” she said. “If I were a superintendent and I didn’t see a fairly good distribution curve within my district, I’d be suspicious about what was going on.”

Under most states’ teacher evaluation systems prior to the most recent round of education reforms – systems crafted with intense pressure from teachers unions – nearly all educators were graded effective and only lost tenure status for the most egregious offenses.

Education reform advocates often argued that it’s virtually impossible for all educators to be effective, and student academic progress revealed that many were not.

Chalkbeat provided some statistics on the DPS educators who are set to lose tenure in the upcoming school year.

“Twenty-eight of the 47 teachers set to lose tenure – or about 60 percent – have more than 15 years of experience. Then of those teachers – 21 percent – have 20 years or more of experience. The majority of the 47 teachers – 26 of them – are white. Another 14 are Latino, four are African-American, two are multi-racial and one is Asian.

“Thirty-one of the 47 teachers set to lose tenure – or 66 percent – teach in ‘green’ or ‘blue’ schools, the two highest ratings on Denver’s color-coded School Performance Framework. Only three – or 6 percent – teach in ‘red’ schools, the lowest rating.

“Thirty-eight of the 47 teachers – or 81 percent – teach at school where more than half of the students qualify for federally subsidized lunches, an indicator of poverty.”

About 79 pecent of DPS schools fall in that category, according to the news site.