Susanna, a 15-year-old, likes to earn spending money by babysitting. She likes kids, so she enjoys her part-time job. She also feels confident that she can handle the problems that sometimes come up when parents are away from home.

Last weekend Susanna was looking after a 5-year-old named Jimmy. They were out in the backyard playing hide-and-seek. Susanna counted to ten, but before she got to the end of the numbers, she heard Jimmy crying.

"OWWW," the little boy yelled. He ran up to Susanna and held out his hand. "I got stung by a bee!"

Susanna stayed calm. She comforted Jimmy, and led him into the kitchen. She talked calmly to the little boy as she ran a clean washcloth under cold water. Then she applied the cold cloth to the red place on Jimmy's hand. Jimmy's bee sting didn't have the stinger left in it. If the stinger had been there, Susanna would have used a fingernail to gently scrape, not pull, it out.

Susanna and Jimmy played quietly inside for a while as Jimmy calmed down. Soon he had forgotten all about his sore hand. But Susanna didn't forget. She watched Jimmy carefully to see if he showed any signs of having an allergic reaction to the sting. But Jimmy's color stayed good, and he seemed fine. If he had gotten sick to his stomach, looked pale, or felt weak, Susanna would have called an adult neighbor for assistance. If Jimmy had had trouble breathing, or had fainted, Susanna would have called 911 for emergency help.

How did Susanna know so much about what to do for a bee sting? She is a certified "Safe Sitter." She took a course and learned about basic safety habits, emergency procedures and good child care. She learned to phone an adult for help whenever something happens that she isn't sure how to handle. She learned never to leave children alone in the house -- even for a minute. And she was reminded that her main job as a sitter is to care for the children, not to do her homework or talk on the phone to friends. When Jimmy was stung, she put the lessons she learned into effect.

These are some of the guidelines Susanna learned in her Safe Sitter course:

*Ask the parents you're sitting for to tell you their children's routines. Find out what they eat, and when, and what time they go to bed. Find out if they take any medicines, and what amounts they need, and when.

*Get a phone number where the parents can be reached while they are out. Also make sure you have a number of a neighbor who knows the family you can call in case you can't reach the parents. Find out what time the parents are expected home.

Dr. Patricia Keener of the Community Hospital of Indianapolis in Indiana designed the course. The first students took it in 1980. Since then, over 2,000 teen-agers in several ifferent states have been certified. This year, the American Academy of Pediatrics, an organization of 28,000 children's doctors, decided to recommend the course. If you or someone you know would like to know more about it, write to the AAP at 141 Northwest Point Rd., P.O. Box 927, Elk Grove Village, Ill. 60007. Other organizations also offer babysitting courses; ask your local Red Cross chapter or Girls Scouts of America troop about their babysitting certificate programs.

Susanna learned some practical tips about babysitting, too. She was taught that:

*Sitters shouldn't let anyone into the house, and should be careful when answering the phone. Don't let the caller know that young people are alone in the house. Instead of saying, "They're out," if someone asks to speak to an adult, say, "They can't come to the phone right now," and offer to take a message.

*Sitters and the children they're caring for should not watch scary movies that might make them afraid of normal house noises.

*Sitters should feel free to call their own family and ask for a ride home if the people they have been sitting for appear to have been drinking when they get home.

Susanna has a reputation as a reliable, careful babysitter. She's popular with the parents and kids in her neighborhood. She's made so much money that she went out last weekend and bought herself tickets to a Bruce Springsteen concert. That's one night she won't be available for babysitting.

Tips for Parents

The American Academy of Pediatrics provides these tips to parents hiring baby sitters: Check the baby sitter's references, training and general health in advance. Allow the sitter to spend time with you in advance to become acquainted with the children and their routine. Show the sitter around the house, pointing out fire escape routes and potential probem areas. The sitter should be told to leave the house immediately in case of fire, and call the fire department from a neighbor's house. Discuss feeding, bathing and sleeping arrangements for your children. Tell the sitter any allergies or specific needs of your children. Leave a flashlight available. Tell the sitter where you can be reached and your expected hour of return.Catherine O'Neill is a contributing editor to the Health section.