FARMINGTON — Most San Juan County schools have maintained a consistent letter grade over the last two school years, according to statewide report card released on Thursday.

But, this year, a drop in letter grades was more common than an increase among schools in the Aztec, Bloomfield, Farmington and Central Consolidated school districts.

Administrators blame changes in the curriculum and student assessments for the lower scores.

The New Mexico Public Education Department on Thursday released the 2013-2014 report cards for the state's 843 schools. Seventy-one percent of schools maintained or improved their grades from the 2012-2013 school year, according to the department's press release.

In San Juan County, 48 schools received grades. Of those, 11 improved their grades over the previous school year, while 13 dropped. The remaining 24 schools saw no change in their grades.

The formula to determine the scores is based on a number of factors, including attendance, college and career readiness, enrollment and reading and math scores from the annual statewide assessments in March.

Schools in CCSD and the Farmington school district saw the most movement, with four schools in each district improving their grades and six schools in each district dropping at least one letter grade.

Three elementary schools in Farmington — Bluffview, Esperanza and McCormick — saw their letter grades drop two levels from a C to an F. Mesa View Middle School and Apache Elementary School dropped from Ds to Fs, giving the Farmington district a total of five failing schools in the 2013-2014 school year.

Farmington schools did not receive any Fs in the 2012-2013 school year.

The district may file protests with the state education department for many of the grades, said Robert Emerson, the district assistant superintendent of educational services and data management.

"The grades don't reflect the performance of our schools," Emerson said.

Emerson said state assessments students took in March were not aligned with the Common Core curriculum the state education department requires districts to teach. The Bridge assessment was designed to be a transition exam for the Partnership for Assessment of Readiness for College and Careers exam. That exam is expected to be implemented in the upcoming school year. It uses 100 percent of the Common Core curriculum.

Depending on the subject, the Bridge assessment used between 30 and 70 percent of the Common Core curriculum and parts of the old state standards, which are not longer taught.

"Students are being tested on things that are not aligned with what we are suppose to be teaching," Emerson said.

Both Farmington and CCSD each have a single school that earned an A. Farmington's Piedra Vista High School maintained its A for a second year, while CCSD's Newcomb Elementary jumped from a C to earn its first-ever A.

The improvement at Newcomb Elementary was mind-blowing, said Matthew Tso, CCSD school board vice president. He added everyone at the school worked together to achieve that score.

"It goes back to staff and teachers, to parents and the students who are at the school," Tso said.

CCSD's Newcomb Middle School rose from a D to an F, leaving Mesa Elementary as the district's sole failing school. Mesa Elementary has received an F for three consecutive years. The district made improvements at the school and hoped it would improve its grade, Tso said, but more work is required.

All four CCSD high schools dropped one letter grade, with Kirtland Central getting a B, Newcomb and Shiprock dropping to Cs and Career Prep receiving a D. Tso said a drop in high school graduation rates affected the schools' grades.

Schools in Aztec and Bloomfield saw minor changes. Naaba Ani Elementary in Bloomfield dropped to a D grade, and Lydia Rippey and McCoy elementary schools in Aztec increased their grades from Cs to Bs.

Bloomfield's Assistant Superintendent Chuck Culpepper said the district is a little disappointed in the grades and thought its schools would see more improvement. But Culpepper was happy most schools maintained their grades.

"With all the changes this year, if we could break even, I am happy," he said.

Aztec Superintendent Kirk Carpenter said he is glad two of his district's elementary schools improved, but he cautioned there is still work ahead.

"Obviously, the work has just started," he said. "We're digging into the grades, down into the details of what is happening and finding out the root causes."

 For more information on school letter grades and to see the complete report card for all schools in New Mexico, go to bit.ly/SchoolGrades

Joshua Kellogg covers education for The Daily Times. He can be reached at 505-564-4627 and jkellogg@daily-times.com. Follow him @jkelloggdt on Twitter.