Philanthropist Bill Gates, co-founder of the Bill and Melinda Gates Foundation. The foundation, which has backed the Common Core State Standards, on Tuesday urged states to delay using Common Core test results to evaluate teacher performance. (Jim Watson/AFP/Getty Images)

The Obama administration is resisting mounting calls for a moratorium on using student test scores to evaluate teachers, students and schools.

On Tuesday, the Bill and Melinda Gates Foundation, which has invested more than $200 million to create, support and implement the Common Core State Standards, said states should hold off from using new standardized tests aligned to the Common Core to evaluate teacher performance.

The foundation joined the two largest teachers unions in calling for a two-year moratorium while students, teachers and school systems adjust to the new standards.

“The standards need time to work,” Vicki Phillips, who heads the foundation’s K-12 program, wrote in an open letter. “Teachers need time to develop lessons, receive more training, get used to the new tests, and offer their feedback. Applying assessment scores to evaluations before these pieces are developed would be like measuring the speed of a runner based on her time — without knowing how far she ran, what obstacles were in the way, or whether the stopwatch worked!”

The Obama administration, which has championed the use of student scores to evaluate teachers, rejected the idea.

Read the letter

Common Core letter

A top official with the Bill and Melinda Gates Foundation urged states to delay using Common Core test results to evaluate teacher performance. Read it.

“A blanket moratorium is not the best approach — just as a one-size-fits-all timeline is not the best solution,” said Dorie Nolt, a U.S. Department of Education spokeswoman. “We believe the most thoughtful approach is to work state-by-state to see what support each state will need, and not to stop the progress states have already made, or slow down states and educators that have been working hard and want to move forward.”

The number of states using teacher-evaluation systems based in part on student test scores has surged during the past five years. Many states and school districts are using the systems to make personnel decisions about hiring, firing and compensation.

The rapid adoption has been propelled by the Obama administration, which made the teacher-evaluation systems a requirement for any state wanting to compete for Race to the Top grants or receive a waiver from No Child Left Behind, the 2002 federal education law.

Thirty-five states and D.C. require student achievement to be a significant factor in teacher evaluations. Ten states do not require that student test scores be used for teacher evaluations.

Phillips wrote that the new Common Core State Standards are yielding positive results in many places, but that teachers are worried about the fast pace of the rollout and testing.

Between 2008 and 2010, 45 states and the District of Columbia adopted the K-12 Common Core State Standards in math and reading, which specify the skills and knowledge every student should possess by the end of each grade. Three states — Indiana, Oklahoma and South Carolina — have since changed course and passed legislation this year to pull out of the standards.

Participating states have committed to giving new standardized tests next spring that will be based on the new standards.

That is worrying many teachers, Phillips wrote.

“As I’ve talked with our partners over this past year, I have heard over and over again their wholehearted support for the Common Core and their very real anxiety about the challenges that come with change,” Phillips wrote. “The teachers’ anxiety is understandable: A rushed effort to apply the assessments could punish teachers as they’re trying new things, and any hiccups in the assessments could be seen as flaws in the standards.”

The call by the foundation for a moratorium echoes similar positions taken by the two major teachers’ unions. Dennis Van Roekel, president of the National Education Association, said consequences should not be attached to the Common Core tests until at least the 2015-2016 school year while Randi Weingarten, president of the American Federation of Teachers, has called for a two-year moratorium on high stakes associated with tests.

The calls come as new research raises doubts about whether student test scores are a valid way to measure teacher quality.

In the first large-scale analysis of new systems that evaluate teachers based partly on student test scores that was published last month, two researchers found little or no correlation between quality teaching and the appraisals teachers received.

The study, which appeared in Educational Evaluation and Policy Analysis, a peer-reviewed journal of the American Educational Research Association, is the latest in a growing body of research that has cast doubt on whether it is accurate to use empirical data to identify good and bad teachers

In April, the American Statistical Association said that teachers account for a maximum of about 14 percent of a student’s test score, and warned states against relying too heavily on test scores to make personnel decisions.