Results for some of the states that participated in Common Core-aligned testing for the first time this spring are out, with overall scores higher than expected though still below what many parents may be accustomed to seeing.

Full or preliminary scores have been released for Connecticut, Idaho, Missouri, Oregon, Vermont, Washington and West Virginia. They all participated in the Smarter Balanced Assessment Consortium, one of two groups of states awarded $330 million by the U.S. Department of Education in 2010 to develop exams to test students on the Common Core state standards in math and English language arts.

Scores in four other states that developed their own exams tied to the standards have been released. The second testing group, the Partnership for Assessment of Readiness for College and Careers, is still setting benchmarks for each performance level and has not released any results.

Even when all the results are available, it will not be possible to compare student performance across a majority of states, one of Common Core's fundamental goals.

What began as an effort to increase transparency and allow parents and school leaders to assess performance nationwide has largely unraveled, chiefly because states are dropping out of the two testing groups and creating their own exams.

U.S. Education Secretary Arne Duncan told state leaders in 2010 that the new tests would "help put an end to the insidious practice of establishing 50 different goal posts for educational success."

"In the years ahead, a child in Mississippi will be measured against the same standard of success as a child in Massachusetts," Duncan said.

Massachusetts and Mississippi students did take the PARCC exam this year. But Mississippi's Board of Education has voted to withdraw from the consortium for all future exams.

"The whole idea of Common Core was to bring students and schools under a common definition of what success is," said Tom Loveless, a senior fellow at the Brookings Institution. "And Common Core is not going to have that. One of its fundamental arguments has been knocked out from under it."

No Child Left Behind, President George W. Bush's signature education law, requires states to test students each year in math and reading in grades three to eight and again in high school. Congress has been debating ways to overhaul the law. The House and Senate have approved differing versions this summer that would maintain the testing requirement but let states decide how to use the results.

The Common Core-aligned tests fulfill the federal requirement, yet are significantly different from the exam that students are accustomed to taking.

Rather than paper-and-pencil multiple choice tests, the new exams are designed to be taken by tablet or computer. Instead of being given a selection of answers to choose, students must show how they got their answer. Answer correctly and get a more difficult question. Answer incorrectly, get an easier one.

Field tests administered last year indicated that a majority of students would not score as proficient in math and reading on the tests. So this summer, states have braced for the results, meeting with parents and principals to explain why the results will be different.

At Los Angeles Unified School District, Cynthia Lim, executive director of the Office of Data and Accountability, said the preliminary results received by the nation's second largest district are "lower than what people are used to seeing." District officials are consulting with school leaders about how to explain to parents and students that new test results should not be compared with old ones.

"I think we are getting richer information about student learning," she said.

Overall, the statewide scores that have been released are not as stark as first predicted, though they do show that vast numbers of students do not qualify as proficient in math or reading.

In Idaho, nearly 50 percent or more of students tested were proficient or above in English language arts. The results were lower for math: less than 40 percent were proficient in five grade levels. In Washington, about half of students across the state earned proficient scores. In Vermont, English proficiency scores hovered below 60 percent and dipped to as low as 37 percent in math.

States using the Smarter Balanced tests are using the same cut scores but different descriptors. What is "below basic" in one state might be "slightly unprepared" in another.

Initially, Duncan said the department would ask the two consortia to collaborate and make results comparable. But while the Smarter Balanced test has four achievement levels, the PARCC exam will have five.

When the testing groups were created, PARCC was a coalition of 26 states and Smarter Balanced 31; some states belonged to both. This year, 11 states and the District of Columbia took PARCC exams. Arkansas, Mississippi, and Ohio have since decided to withdraw from the exams. Eighteen states participated in the Smarter Balanced test this year. Of those, three states have since decided to abandon one or all of the grade level tests.

"It's always disappointing to have a state drop out," said Kelli Gauthier, a spokeswoman for Smarter Balanced. "But we feel really confident in the group that we have."

Sarah Potter, communications coordinator for the Missouri Department of Elementary and Secondary Education, said the frequent changes in which test will be given and what students will be tested on has frustrated teachers and parents. The state participated in Smarter Balanced this spring but lawmakers have appropriated $7 million to develop a new state-based assessment plan.

"We are losing that that state-to-state comparability after this year, unfortunately," Potter said. "But our Legislature has said we should have Missouri standards so that is the route we are taking."

Aside from the defections, the exams have also experienced from technical glitches and an opt-out movement that surfaced this spring. Results in Nevada, Montana and North Dakota were hit with widespread technical problems; Nevada counted last year's scores a total loss.

In Oregon, slightly more than 95 percent of students took the exam, just making the federal requirement for participation. For black and special education students, as well as some districts, the requirement was not met, meaning the state could potentially lose federal funds.

Most states have not been able to release test scores before the start of classes, a delay that was expected in the exam's first year, but nonetheless frustrating for some teachers and parents.

"From a high school senior's perspective, it's gotta be really tough," said Renata Witte, president of the New Mexico PTA. "You want to get those college applications in and you need this information to complete them."