The number of "A" schools fell from 73 in a preliminary assessment in January to 39. The number of F schools also dropped, from 89 to 69.
All the grades were calculated by the statea Public Education Department based on a formula it devised to measure performance and progress.
Martinez hailed the results as a step forward, especially compared to the old federal rating system that she said unfairly downgraded New Mexico schools.
Under the U.S. government's No Child Left Behind Act, about 98 percent of New Mexico's schools would have received failing grades for the year, Martinez said. The state recently received a waiver from the U.S. Education Department releasing it from the No Child Left Behind Act.
Martinez, during a news conference at Route 66 Elementary School, said the state system of grading schools A through F is clearer and much more accurate than the federal government's model.
No Child Left Behind is a pass-fail system, meaning a school could excel in every category but one, yet that would lead to a failing grade, Martinez said.
In addition, the federal ratings bypassed more than 20,000 New Mexico students for various reasons, such as disabilities or the fact that they were learning English as a second language.
In contrast, the state's A-F grading system means accountability for every child and every school, Martinez said.
Hanna Skandera, secretary-designate of public education, said the first round of official grades shows that schools lost ground with the lowest-performing students.
But of 14 classes measured statewide in math and reading, 11 were up overall, Skandera said.
Like the governor, Skandera said parents and taxpayers could trust that the new grading system is more truthful than No Child Left Behind.
"We do have some failing schools, but not 98 percent," she said.
The grades break down this way:
39 schools received an A.
198 got B's.
275 received C's.
250 got D's.
69 received an F.
In the state system, those in the bottom tier will have a clearer idea on what they need to do to improve, Skandera said.
She said school grades would be calculated on three years' worth of data whenever possible to make sure that no school was penalized because of a single test or an off day.
As part of the grading system, the Public Education Department surveyed 190,000 students as to what their schools could do to improve. Martinez said this data also should be valuable as school staffs strive for higher grades.
Martinez said school grades were just one of three reform measures the state should implement to upgrade public education.
She said again she would push in the next legislative session for bills to reward "the best and brightest teachers" and for retention of the bottom tier of third-graders in reading.
Current law allows a parent to override a school staff one time if it wants to hold back a child. Martinez has pressed during her 18 months in office for state-mandated retention of those children who are not reading proficiently at the end of the third grade.
The bill has been controversial. Rep. Mimi Stewart, D-Albuquerque, said states such as Florida with forced retention programs actually see more kids drop out of school.