School cafeterias are much criticized for offering the kind of snack foods and desserts that contribute to childhood obesity. But banning junk food from cafeterias, as some schools have tried, or serving only escarole or tofu, can backfire. Students then skip lunch, bring in their own snacks or head out for fast food. We’ve even seen some pizzas delivered to a side door.

Children and teenagers resist heavy-handed nutritional policies — and the food that is associated with the heavy hand. No food is nutritious, after all, until it is actually eaten.

A smarter lunchroom wouldn’t be draconian. Rather, it would nudge students toward making better choices on their own by changing the way their options are presented. One school we have observed in upstate New York, for instance, tripled the number of salads students bought simply by moving the salad bar away from the wall and placing it in front of the cash registers.

Experiments that we and other researchers have done in cafeterias at high schools, middle schools and summer camp programs, as well as in laboratories, have revealed many ways to use behavioral psychology to coax children to eat better. Here are a dozen such strategies that work without requiring drastic or expensive changes in school menus.

Click on the information icons to read about the lunchroom strategies.