A tougher test - coupled with stricter standards for evaluating the students who take it - has prompted a steep decline in this year's scores on the state's main school-achievement exam, as well as a surge in the number of children failing to earn a "proficient" rating.

The news that the Pennsylvania System of School Assessment (PSSA) test scores fell for a fourth consecutive year has also sparked a growing debate over the fairness of using the falling scores from a changed test to evaluate teachers and struggling public schools.

State officials acknowledge that the test questions have grown harder, to align Pennsylvania with the national learning standards known as Common Core. But they say the lower 2014-15 scores - from English and math tests of students in grades 3 through 8 - are not an "apples-to-apples" comparison with past years, and that the Wolf administration does not want standardized exams to be the sole measure of teacher and student performance.

Critics still question the new standards.

"How can you say students did worse or better now than in previous years if in previous years, scoring was based on certain levels of proficiency, and now there are new ones?" said State Sen. Andy Dinniman of Chester County, the ranking Democrat on the Education Committee.

Students in grades three to eight scored an average of 35 percent lower in math and 9 percent lower in English this year.

Pennsylvania Education Department spokeswoman Nicole Reigelman said in a statement, "It is important to remember that Pennsylvania's students haven't changed - the assessment has changed. Due to the increased rigor of the standards, a dip in scores is anticipated.

"These new PA Core Standards were officially approved in the autumn of 2013, and transitioning to the new standards takes time, curriculum development, and resources. Over the next several years, PDE anticipates student performance will grow steadily as resources return to the classroom, and students and teachers become more familiar with the PA Core."

Last week, the state Board of Education voted to make scoring more difficult as well, setting new cutoffs for the test ratings: below basic, basic, proficient, and advanced.

In "English Language Arts," for instance, the new "cut scores" will require an eighth-grade student to score 1130 or above to be graded "advanced." Scores of 1000 to 1129 will earn "proficient," 886 to 999 "basic," and 600 to 885 "below basic."

Reigelman said the department had only the aggregate data used to recommend the cut scores. More detailed data will not be available for several weeks, she said.

The biggest impact could be on teacher evaluations, since teachers are rated in part on student performance, educators said. Lower scores could lead to lower evaluations.

"When teachers, particularly in schools that serve impoverished communities, have students in overcrowded classes and score lower on standardized tests, that impacts teacher evaluations," said Wythe Keever, a spokesman for the Pennsylvania State Education Association. "The continuing obsession with standardized tests has to change."