South Carolina's elementary and middle school students posted worse overall scores on state-standardized tests last spring across all grades compared to 2013.

The Education Oversight Committee says students' scores are disappointing, but drops in math and reading were expected as teachers transitioned to new benchmarks for what students must learn.

Passing rates on the state's Palmetto Assessment of State Standards, known as PASS tests, range between 63.5 percent in third-grade science to 83.7 percent in fourth-grade social studies. The tests are taken by third- through eighth-graders in five subjects: writing, reading, math, science and social studies. The end-of-year, high-stakes tests help determine how well students are progressing toward state and federal education goals.

State educators and politicians were still reacting Wednesday to the unusual way the state Department of Education released the test scores. The department in the past has given the test score information to districts and the media on an embargoed basis, to give stakeholders time to review the data and provide reaction and context.

Instead, the agency quietly posted the data on its website, marking a first since South Carolina students began taking high-stakes tests in 1999. The state Board of Education said the lack of notification or explanation on what the scores mean amounted to a public disservice.

The percentage of students passing statewide fell in 22 of the 30 total tests taken. The worst drops occurred in sixth- and seventh-grade reading, to 69.3 percent and 68.1 percent passing, respectively. Both declined by 5.1 percentage points from 2013 rates.

The biggest increase came in third-grade writing, which jumped 7.8 percentage points to 78.1 percent passing. This is only the second year students have taken a PASS writing test.

Scores fall into three categories: "not met," "met" and "exemplary," with the latter two deemed passing.

Superintendent Mick Zais highlighted that the percentage of students earning "exemplary" scores increased across all five subjects.

"These kinds of test results are exactly why Governor Haley introduced and passed the biggest education reform package in the history of our state this year - and why we have to recommit to improving how we educate our children every single year," said Doug Mayer, spokesman for Gov. Nikki Haley.

Charleston County Schools Superintendent Nancy McGinley said Wednesday that she was pleased that the percentage of Charleston school district students who scored exemplary in all subjects was greater than the state average at all grade levels, and also was encouraged by the improvements in 3rd and 5th grade writing.

"It is well known that states across the country who implemented Common Core State Standards and Assessments saw a decline in test scores and the State of South Carolina and Charleston County are no different," McGinley said. "While our decreases in ELA (English language arts) and Math are disappointing, we expected to see slight dips as the rigor has increased and we bridged the former assessment with the new standards."

Full implementation of the standards is occurring this school year, and students will take new tests aligned to those standards next spring.

That will likely result in big drops, similar to what happened in other states that have already fully implemented the standards, the spokeswoman for the Education Oversight Committee, Dana Yow, said Wednesday.

"Some of these losses can be attributed to the implementation of Common Core, but most of them can be attributed to our failure to provide every student a 4-K education," said Christian Hertenstein, campaign spokesman for independent gubernatorial candidate Tom Ervin. "We also need to commit to a curriculum and dedicate resources to its success. We spend $6,000 more per inmate than we do per student. We don't need Common Core, we need common sense."

McGinley said the district has invested time and resources for teacher development and that investment has led to improvements.

"We plan to expand and strengthen our support and offerings to our teachers delivering math and science instruction and will have an accelerated training plan in place shortly after the school year begins," she said.

"The standards and assessments require a higher depth of understanding by the student," the EOC said in a two-page statement on the scores Tuesday. "It is important to remember that the academic skills and knowledge required of these standards and assessments are to ensure that students will be ready for college, careers and life in the 21st century."

Schools with large percentages of poor and minority students posted the biggest declines. Instances of narrowing gaps can often be explained by lower overall achievement, according to data from the agency.

Zais, on the other hand, pointed to progress among students with disabilities. Achievement gaps for that group narrowed in 24 of the 30 total tests taken.

Math and reading standards will change again in 2015-16, as required by a new law pushed by Common Core opponents and signed by Gov. Haley. But they still must be certified as preparing students for college and careers. Zais initially said he would direct state writing panels that began meeting last month to ignore the current standards. But agency officials said last week the law doesn't allow that, and Common Core standards will be on the table.

Republican Molly Spearman and Democrat Tom Thompson are running for Zais' seat in November; neither campaign could be reached for comment. American Party candidate Ed Murray is also running.

Post and Courier reporters Jeremy Borden, Amanda Kerr and Cynthia Roldan contributed to this report.