NEWTON, Mass.

IT HAPPENS all too often. We’re harried, stressed and doing a dozen things at once. Maybe we’ve left a toddler in the car “just for a minute” to dash into the dry cleaner, the ATM, or the post office. Or left a child in the back seat in the driveway while we unload groceries in the kitchen. Or we’ve read the ghastly stories of babies missing for hours, forgotten in the day-care-center van.

For some children, being left alone in a car has been fatal, as it was last month for three-year-old James Lymburner in Warwick, who climbed into the family car and died of heat-related causes, leaving his family devastated (“I don’t know why this happened,” news, June 10).

Every year we learn of children who have died from heat stroke in parked cars. So far in 2009 these include a child in California left in a car at a train station, a seven-month-old in Texas, whose mother left him behind, a toddler in Florida, whose mother forgot to drop him with the sitter, another in Washington State, overlooked by his mother, who went to work; an infant in Milwaukee left behind in the day-care-center van, and a one-year-old boy left in the van by a day-care operator in North Carolina.

Each of these tragedies is unique, but they all share two characteristics: All were predictable and all could have been prevented. In fact, we can reliably predict that 35-40 children will die this summer in oven-hot cars. Even on a mild summer day, the family car can quickly become too hot. When it reaches 90 degrees outside, the temperature inside a car can reach 125 degrees in minutes, with a young child’s body temperature increasing five times faster than that of an adult.

A national study by the Massachusetts-based Education Development Center examined 171 heat-stroke deaths from 1995 through 2002 and found that nearly 39 percent were attributed to a parent or caregiver’s forgetfulness, and 27 percent were the result of unattended children playing in unlocked vehicles. EDC has continued to monitor these tragedies, finding that although the deaths keep occurring — 212 additional children at last count — the patterns have not changed.

Such tragic events nearly always involve children under the age of four. They have occurred in 47 states, to single parents, two-parent families, upper-middle class and poor, well-meaning parents, and responsible adults. Families who buckle up their children to keep them from harm, who wouldn’t dream of leaving their children alone in the bathtub or beside a swimming pool, think nothing of leaving them locked in a vehicle.

Thirteen states have passed laws making it illegal to leave a child unattended in a vehicle and a dozen more are considering such legislation. New technologies beckon, such as cooling gels in child safety seats, alarms to alert a driver when a child is left behind, or motion sensors for the back seat. But no device substitutes for adult supervision, for arranging with your day-care provider to call one another if your child is absent, and for keeping your vehicle locked when not in use.

Local officials insist that if you see a child unattended in a car, you must not hesitate to call 911.

A generation ago, children suffocated in abandoned refrigerators and freezers. Through a combination of new technology (magnetic seals instead of locks), laws that require removing the doors when disposing of these appliances, and, ultimately, a change in our own behavior — this particular cause of death has been erased.

The same approach needs to happen with the family car. We need to change our attitude of what is appropriate and what is safe. A car is not a playground, a babysitter, or a safe place to leave children — even for “a minute.”

Anara Guard is a senior researcher at the Education Development Center, an international nonprofit education- and health-research group based in Newton, Mass. ( www.edc.org).