There’s a new twist for students seeking magnet seats in Charlotte-Mecklenburg schools: They’ll have to rely on last year’s test scores to get into programs with admission requirements.

Charlotte-Mecklenburg Schools requires passing scores in math, science and/or reading for admission to International Baccalaureate, world language and STEM (science, technology, engineering and math) magnets. Normally students are placed during the January lottery but can lose their seat after testing in May or June if they don’t make the grade.

This year, though, North Carolina won’t know who passed the 2013 exams until October. The state is rolling out a whole new set of tests, and state officials say it will take that long “to allow for the necessary statistical analyses and standard-setting process.”

The fallback plan for magnet admissions is just one of the ways the new testing program is rippling into the lives of students and teachers.

“It’s sort of a double whammy,” said CMS magnet director Jeff Linker, noting that the statewide rollout of a new student data-tracking system further complicates planning and placement.

The new exams are linked to national Common Core standards for reading and math, and to new state standards for other subjects.

The goals are lofty: Launch a rigorous curriculum that better prepares students for global competition. Replace multiple-choice tests with exams that give a more sophisticated measure of problem-solving and high-level thinking. Use the data to improve teaching.

But the transition is going to be rocky. Consider:

The N.C. Board of Education this week voted to waive its requirement that high school end-of-course exams count for 25 percent of a student’s final grade. That rule is designed to ensure that students take the exams seriously.

The waiver means each school district must figure out how to use the state exams this year. They could opt to use a test designed by the teacher or district for final grades, but that means double-testing.

“This change will affect students and teachers in EOC courses,” CMS Superintendent Heath Morrison said in a memo to school board members Friday. “We will bring a recommendation to the board at the Dec. 11 meeting on this issue.”

This year, the state is also setting aside its requirement that students who fail state exams on the first try take them again. That’s because no one will know who failed until the next school year is under way.

With the 2013-14 magnet lottery looming next month, CMS officials had to figure out how to handle admission requirements without timely 2013 scores. “I’ve been scratching my head over that for most of the fall,” Linker said Friday.

CMS added the admission requirements in recent years to make sure students in specialty programs have the basic skills to keep up with the classes. Students must pass reading and math for IB admission, math and science for STEM admission and reading for world languages.

Normally, for instance, an eighth-grader hoping to enter Phillip O. Berry Academy Technology as a freshman would have to pass math and science this spring. This year admission will rely on a passing score in seventh-grade math (science isn’t tested in seventh grade).

Linker said CMS considered using results from teachers’ exams this year, but that wouldn’t be consistent from school to school. Using last year’s state results isn’t perfect, he said, but “it’s the best data we have to work with.”

The advantage, he said, is that students won’t face unpleasant summer surprises. If they didn’t meet the requirements last year, they will know to seek another option earlier in the year. CMS has many magnets that don’t require grade-level scores, and students can always attend their neighborhood school.