SOUTH PORTLAND — James O. Kaler Elementary School on South Kelsey Street received an F grade and the seventh-lowest cumulative score in the state Wednesday as Gov. Paul LePage and Education Commissioner Stephen Bowen handed out the first-ever letter grades for Maine public schools.

With School Superintendent Suzanne Godin unavailable for comment, School Board Chairman Rick Carter said the grades did not surprise him.

“We have already seen all of this, we know we are struggling with the English language learners,” Carter said.

The grades, reflecting academic performance in the 2011-2012 school year, are based on assessment test scores and progress made by students. They are considered a benchmark by Bowen, but not a fully accurate measure of student achievement.

Letter grades were compiled by adding math and reading proficiency scores on a scale of 100; three-year average academic growth on a scale of 100, and academic growth by the bottom quarter of students on a scale of 50, for a maximum of 400 points.

“We understand a letter grade does not tell the whole story of a student, nor does it tell the whole story of a school,” Bowen said, vowing the grades would lead to increased assistance for under-performing schools.

Pond Cove Elementary School, Cape Elizabeth Middle School and Cape Elizabeth High School all garnered A’s. In Scarborough, the middle and high schools got A grades, and Wentworth Intermediate School, serving third- through fifth-graders, received a B.

City elementary schools spanned the grading gamut, from an A for Helena H. Dyer Elementary School to the F received at Kaler. Dora L. Small School received a B, and Frank I. Brown and Waldo T. Skillin schools were given Cs.

South Portland High School received a B, and the city middle schools each earned Cs.

Reading scores at Kaler showed the “bottom quarter” of students progressed at the lowest rate, scoring 16.5 out of 50 points. Students in the bottom quarter in math also progressed slowly, scoring 21.6 out of 50.

In terms of overall perfomance, the school scored 40.7 out of 100 in math and 43.9 of 100 in reading. The total score of 169.3 of 400 was seventh-lowest of 422 schools graded.

Carter noted scores and grades were reduced in areas with higher concentrations of students learning English as a second language and where higher percentages of students are receiving free or reduced-cost lunches.

“It is not a surprise the wealthier neighborhoods did better,” Carter added.

Using the test scores as a basis for the grades runs counter to what the state is looking to reform, Carter said.

“Part of the problem I have is this goes against what DOE is doing to get us to go to proficiency-based rating,” he said.

Bowen said the grades are part of a wider effort to increase transparency about public school performance at what is called the online “data warehouse.” Thirteen other states and New York City now assess school performance with letter grades, he added.

Carter placed less value in looking back than did Bowen, especially as city schools establish new methods for proficiency based learning.

“If you looked at the system they put forward, is that how you would judge if a school is doing well or not doing well?,” he said. “I would rather see a system about what projects student growth.”

David Harry can be reached at 781-3661 ext. 110 or dharry@theforecaster.net. Follow him on Twitter: @DavidHarry8.