Sometimes, Yajaira Rivera would storm out of school in frustration during the middle of the day.

Other times, she was told to leave.

And then there were the many days she simply stayed at home, avoiding both trouble and the classrooms where she was falling behind.

As a seventh-grader last year at Nobel Elementary School in Chicago, Yajaira missed 68 days out of 170. She'd already lost an additional 213 days since second grade, far more than a full year of classes, records show.

But Yajaira is not just any difficult student needing discipline. She is coping with learning and emotional disabilities that explain why a child described as "motivated to learn" by a school social worker has so many conflicts with teachers and fellow students.

Attendance data provided by Chicago Public Schools show that students like Yajaira who are diagnosed with a learning or emotional disability — and there are thousands of them in grades K-8 — miss far more school days on average than children without a disability.

That disparity, along with the details of Yajaira's school experience, raise questions about how the district is handling the difficult but vital task of giving these students a shot at a decent education and a real future.

Education experts note that there are effective strategies for managing and nurturing students like Yajaira. But too often, disability advocates say, officials simply push these youth out of school or let them slip away.

A 2012 Nobel school report provided by Yajaira's family states that "an intervention for minor infractions has been for her mother to bring or keep Yajaira home with her in order to avoid further escalation of Yajaira's anger and behavior."

That intervention — which advocates for the disabled called a potential violation of federal law — "has resulted in poor exposure to the general education curriculum," the school's report noted.

Yajaira's mother, Maria Figueroa, told the Tribune that she reached "an agreement with the principal at Nobel: When Yajaira is upset, I will not send her to school."

Nobel Principal Manuel Adrianzen denied that, telling the Tribune in a written statement: "We have always worked hard to help this parent and her daughter and at no point did I or any member of my staff ever tell her to keep her child at home."

CPS spokeswoman Robyn Ziegler also disputed that Nobel staff allowed Yajaira to miss school as an intervention strategy.

"Behavior management is not a valid cause of absence," she said in a statement.

Whether or not Yajaira's absences were condoned by Nobel administrators, her case fits into a grim pattern.

Consider the 17,000 students in grades K-8 whose "primary diagnosis" in CPS' database is a learning disability — a disorder generally affecting the ability to use or understand language. On average, each of these students racked up two weeks of truancy and excused absences in the 2010-11 school year — about 20 percent more than those with no disability.

Also frequently gone from school were the 1,500 elementary students with an emotional disorder as their primary diagnosis — children whose behavior or feelings impede their learning and ability to get along with others.

On average, K-8 students with an emotional disorder missed about four weeks of school because of truancy and other absences, the Tribune's analysis found. They also accrued 10 times as many suspension days as children without a disability.

Federal law requires schools to provide these students with counselors, aides and other support to help them succeed, and it specifically protects students with disabilities from being excluded from school through excessive suspensions or informal push-outs.