The Rochester School Committee learned students beat state averages on the MCAS tests. However, performance declines in Grade 4 and 5 prompted questions this week.

The percentage of students who scored in the “needs improvement” category in Grade 5 science and technology jumped from 28 percent in 2012 to 32 percent this year. Grade 4 mathematics students who scored in the same category rose from 34 percent last year to 45 percent in 2013.

Assistant Superintendent of Instruction and Curriculum Elise Frangos said students grappled with new test changes.

“I would call this a year in transition in so many different ways,” she said. “A lot is based on open response writing. We’re starting to see common core be much more heavily weighed to open response writing…These are significant shifts.”

Frangos said other changes, such as a switch to a new science teaching method and a new principal, also took place this year.

Frangos and Rochester Memorial School Principal Derek Medeiros unveiled the test results at the committee’s Nov. 7 meeting.

Another drop occurred in the grade 4 English language arts scores. Students who placed in the “advanced” category fell from 12 percent in 2012 to 4 percent in 2013.

Medeiros explained there was a “major shift” in that section of the test. Instead of one long composition piece, students were required to write two long pieces, which staff will address this academic year.

“Not to say that’s an excuse, but it’s a big transition in the way we teach and it’s a huge comprehension challenge [for students] as well,” said Frangos.