NEWBUYRPORT — The state is offering school districts across the state another way to measure student achievement on the Massachusetts Comprehensive Assessment System test, and it shows city schools are moving in the right direction.

While formerly the only means of tracking a school's annual progress has been identifying whether it achieved Adequate Yearly Progress, a new "Growth Model" measurement system released early this week provides more in-depth information on the progression of individual students as they move grade by grade through the school system.

"I think we are showing high growth in some areas, which is very positive," said Newburyport curriculum director Angela Bik yesterday. "Even if we still have students achieving below the level we would like to see, if they are showing significant growth, we know we're moving in the right direction."

According to a district report released Tuesday, school and district growth reports are developed by aggregating the student growth percentiles for all students in the school or district to determine the median student growth percentile. Results are calculated only for students in grades 4 through 8 who have two or more consecutive years of MCAS results and students in grade 10 with MCAS results from grade 8.

High growth is defined as growth in a subject at or above the 60th percentile, typical growth is between the 40th and 60th percentile, and low growth is below the 40th percentile.

Newburyport showed growth in the typical to high range, according to the report. The biggest jumps were in math, grades 7, 8 and 10, where a growth rate of 78 to 81 percent was measured, and in seventh-grade English where student scores jumped 75 percent over previous years.

Bik said the growth tracking is the result of a Department of Education initiative meant to give a broader view of how schools are meeting the challenge of making sure students are proficient in subject areas by 2014, as mandated by the No Child Left Behind Act.

"What the growth model is measuring is individual student progress, but it is measuring that progress by tracking the scores of the same students from one year to the next within a group that scored very similarly," Bik said. "MCAS scores and AYP determinations are all based on student achievement and not necessarily growth, and this gives us another indicator to look at."

The newly released growth model is one schools throughout Massachusetts were hoping to see implemented, as more and more schools struggle to meet the tough standards set by the state.

"The state was really feeling the need for additional information also because there were some contradictions in the way our AYP scores were looking as a state, compared to the way our students were scoring on national normative tests," Bik said. "We have some of the highest standards in the country for our MCAS testing. Our (standards) are high, and I think that's a positive thing, but it's also going to make it tougher to make those AYP standings. We're scoring some of the highest scores in the country and the world; it doesn't make sense we're unable to reach AYP."