PARENTING : Curing Monday Morning Flu : It takes a little detective work to determine if a child is truly ill--or worried sick about school.

“My head hurts.”

“My tummy aches.”

“I don’t feel good!”

It happens every Monday morning.

The whining starts as soon as the alarm goes off.

You know the drill. You pull out the thermometer. You check for symptoms. No fever. No vomiting. No diarrhea.

When children repeatedly claim--or feign--illness, parents are presented with a quandary. No one wants to force a sick kid to go to school. But keeping a healthy youngster home is no good either. How can a parent determine if a child is truly ill or simply trying to get out of going to school?

“Parents must be concerned detectives,” said Robin Schleifer, school nurse at Portola Middle School in Tarzana. “Pay attention to what the child looks like, if they have a fever, what their eyes look like, how their attitude is, if they are eating and if they have regular bowel habits.”

Pediatrician Robert Barnhard, who has offices in Agoura and Tarzana, also recommends an initial visit to a physician. “Headaches and tummy aches are the most difficult complaints for parents to evaluate,” he said. “If they are occurring over and over, parents should seek medical attention to rule out possible illnesses, such as sinus infections, vision problems, irritable bowel syndrome, constipation or appendicitis.”

If the youngster gets a clean bill of health, the parent must do some investigating to figure out why the child goes to such lengths to avoid class. A schoolyard bully, impending exam or the prospect of getting called on in class may have a child terrified. New kindergartners and first-graders, as well as students beginning middle or junior high school, often feel anxious about being separated from their parents.

Children who complain about aching heads and bellies are probably really hurting. Fear and anxiety can cause a youngster to be worried sick, according to Glendale pediatrician Vincent Haynes.

“Even though the physician cannot find an organic problem in a physical exam or lab work, an uptight child can experience real discomfort,” he said. “Sit down and talk with the child. Ask what they don’t like, what makes them afraid, what makes them uncomfortable. See if you can pull out what the child is fearful about.”

But while parents should be sympathetic and understanding, experts agree that a well child should not be permitted to stay home.

“It is really important to nip school refusal in the bud,” said Dr. Mary Moebius, a Tarzana child psychiatrist. “If a parent lets the child stay home with the TV going, the kid just loves it, and that night the kid gets ‘sick’ again because he wants to stay home the next day.”

Well, you can lead a kid to school, but getting him to stay in class is another story. Take San Fernando parent Alicia Gonzalez. Last year, her son, Isaac, 11, began complaining that he didn’t feel well. After a doctor confirmed that the boy was fine, Gonzalez sent him to school and headed to work. But just as she settled at her desk, the phone rang. It was the school nurse’s office, where Isaac sought refuge at least three days a week.

“Of course, I picked him up immediately--at first,” Gonzalez said. “But when it continued, and Isaac realized I was on to him, he would tell the nurse, ‘Don’t bother my mom. Call my grandma.’ I would come home from work to find out that my mother-in-law had picked him up from school that morning.”

Isaac finally fessed up to the source of his concern: A bigger, older boy was picking on him. Armed with that knowledge, Gonzalez asked the school principal to intervene. The bullying stopped, and Isaac’s headaches and stomachaches disappeared.

Like Isaac, kids who are intent on staying out of school often end up in the nurse’s office.

“They come in right before the 8 a.m. bell rings,” Schleifer said. “Sometimes they make it through homeroom. Then they tell the homeroom teacher they have to go to the nurse. One girl would make it through the first two hours. Then she would come in right after nutrition. She just didn’t want to be in school. Other kids who are afraid of a certain teacher or certain classes, such as math or P.E., will always come in during the same time and day of week. They say something like, ‘I just need to lie down for one hour.’ ”

In such cases, Schleifer will call the parent to work out an agreement. “The parent and I may set ground rules that if the child has no obvious signs of illness, I will send him back to class without calling home,” she said. “Sometimes if the kid knows that Mom and I agree, that is all it takes to stop the pattern.”