'HOW to Avoid Kindergarten Burnout" has not yet become a hot topic for women's magazines and self-help books. Nor has the market been flooded with articles on preschool panic, sandbox stress, and toddler tension. But don't laugh. Now that childhood stress is emerging as the latest "syndrome," these could be the trend stories of tomorrow.Across the country, anti-stress programs rank as the latest additions to school curriculums. Relaxation has become the fourth "R." Children barely old enough to tie their shoelaces are practicing deep-breathing exercises under the direction of "relaxation teachers," who instruct them to switch on their mental TV sets and imagine a tranquil scene. Other teachers direct students to give each other neck rubs or stretch out on the floor. Until recently, teachers might have encouraged fidgety students to let off steam by running around the playground. Now stress-reduction exercises use a deskbound approach. Four elementary schools in Prince Georges County, Md., offer classes called Introduction to Stress, which sounds more like a college psychology course than a grade school project. The schools claim the classes help students get higher math and reading scores. Not surprisingly, some parents object, complaining that the techniques encourage students to escape from reality. Other parents worry that guided imagery constitutes a form of mind control, at odds with families' religious beliefs. So controversial are relaxation programs, in fact, that certain school districts require parental consent. During the 1980s, stress became a fashionable malady. If you're not stressed-out, the reasoning goes, you must not have an important job. Stress consultants describe "good" stress - a pep pill for the psyche - and "bad" stress, a real downer. They distinguish between female stress and male stress. Even pets, they claim, are tense, perhaps because they live with uptight owners. And then there are children, for whom pressure starts earlier and earlier - sometimes even before birth. A Seattle company called Prelearning, Inc., now markets a "cardiac curriculum" of sonic patterns to stimulate the brain of an unborn child. A pregnant woman straps on a belt with two speakers that will play a series of 16 audiotapes, helping to give her baby a head start in the womb. Later, in the crib, there will be toys for visual and sensory stimuli, followed by parental coaching on how to pass an interview for admission to the "right" nursery school. And on it goes. Perhaps no one should be surprised that all this pressured precocity - coupled with widespread divorce, shifting child care arrangements, and family financial pressures - sends well-meaning educators searching for ways to soothe their young charges. But to enshrine stress in a curriculum and settle for a quick fix - a massage here, a moment of meditation there - pushes children into adult behavior. Relaxation itself turns into a prescribed duty. Childhood recedes. Even if deep breathing and massage prove effective in temporarily calming students, these techniques never deal with the root cause of whatever anxiety children feel. Behind every child under stress fidgets an adult, creating or at least communicating stress. Stress is a climate where the pressure climbs too high for everybody - parents, teachers, and finally children. If the fast track is not to become the only track, from hyperactive children to hyperactive retirees, an old joke will have to be revived in all seriousness: Hurry up and slow down.