Obesity Report Cards:

Math: A; English: B; History: A; Spanish: B; Body Mass Index: F

It seems that some schools are joining the obesity police. The NYT reports that some school districts send home report cards on how children fare on the "Body Mass Index," a crude measure of obesity. Children that are above the 85th percentile on the BMI are considered "obese," or at risk of obesity. Pennsylvania, for example, requires BMI reporting for children in K-8.

The practice of reporting students' body mass scores to parents originated a few years ago as just one tactic in a war on childhood obesity that would be fought with fresh, low-fat cafeteria offerings and expanded physical education. Now, inspired by impressive results in a few well-financed programs, states including Delaware, South Carolina and Tennessee have jumped on the B.M.I. bandwagon, turning the reports — in casual parlance, obesity report cards — into a new rite of childhood.

Legislators in other states, including New York, have proposed them as well, while some individual school districts have adopted the practice. . . .

Even health authorities who support distributing students' scores worry about these inconsistent messages, saying they could result in eating disorders and social stigma, misinterpretation of numbers that experts say are confusing, and a sense of helplessness about high scores.

"It would be the height of irony if we successfully identified overweight kids through B.M.I. screening and notification while continuing to feed them atrocious quality meals and snacks, with limited if any opportunities for phys ed in school," said Dr. David Ludwig, director of the Optimal Weight for Life program at Children's Hospital Boston.