Wake is asking the state Court of Appeals to overturn a lower court ruling that bans the use of mandatory year-round schools. School leaders say that ruling has lead to empty seats in year-round schools and overcrowding in some traditional-calendar schools.

But the lawyer for Wake CARES, the parent group that sued the school district, told the three-judge panel that state statutes guarantee every child the right to attend a traditional-calendar school.

Some parents who sued the school system want the county to give up plans to open all new elementary and middle schools on a year-round calendar. Many also hope school leaders will have to return to a traditional calendar at 22 schools that switched this year to a year-round schedule.

Wake school officials say they needed a year-round schedule at the 22 schools to keep up with enrollment growth. Year-round schools can hold more students than traditional schools by dividing students into four groups with three groups in class at all times.

Many families object to the year-round calendar, which eliminates the long summer vacation in favor of shorter breaks throughout the school year.

Wake CARES filed a lawsuit in March arguing that requiring only some students to attend year-round schools violates the state constitution's guarantee of a "uniform system" of schools with "equal opportunities" for all students.

Wake County Superior Court Judge Howard Manning Jr. sided with Wake CARES in May. He focused on a state law that says school systems shall offer a "uniform term of nine months." He said the General Assembly hadn't given Wake the specific authority to set a school term longer than nine months.

School officials, however, say the state gives them the authority to operate year-round schools. They cite a 2004 state law exempting year-round schools from a requirement that classes start no earlier than Aug. 25.

And they say the state grants local school boards the "complete authority over the assignment of students in schools within their districts."

To the annoyance of some parents, the school district went through with the year-round conversions.

It complied with Manning's ruling by mailing letters to parents of more than 30,500 students asking for consent to send their students to year-round schools, as well as those that follow a modified calendar. Students whose parents declined to grant the consent were sent to traditional-calendar schools.

School officials said 90 percent of the families gave their consent. But the refusals of 2,900 students were enough to create crowding at traditional-calendar schools.

A majority of the students who left year-round schools were from low-income families, upsetting the school district's diversity efforts. That's why the Coalition of Concerned Citizens for African American Children, a local parent group, is backing the school district's appeal of Manning's ruling.

The Court of Appeals has 90 days to issue a ruling, but it could act sooner due to the importance of the case.

The timing of the ruling could still have an impact on the reassignment plan that was presented on Tuesday. That plan called for moving 6,824 students to different schools this fall.

Although the school board is scheduled to vote on the reassignment plan on Feb. 5, administrators say they will wait until March before issuing consent forms for year-round schools, potentially allowing the school board to move the families back for the 2008-09 school year.

Rosa Gill, chairwoman of the school board, said they haven’t discussed whether they’ll still issue the consent forms if the Court of Appeals rules they’re not necessary.