It’s back-to-school season, meaning that pretty soon, about 30 million students will be eating school lunch, and 15 million eating school breakfast, every day. And, just like at our own home dining tables, with all of these meals comes an unfortunate consequence—nearly 530,000 tons of uneaten food every year. In June, the USDA issued a memo reminding schools of the “offer versus serve (OVS) flexibility” as one way to reduce this food waste while also empowering students to select a meal that they like. So what is OVS flexibility, and why does it matter?

Here are three questions—and answers—about OVS flexibility, featuring insights from Diane Pratt-Heavner, spokesperson for the School Nutrition Association.

What is offer versus serve (OVS) flexibility for school lunch?

The National School Lunch Program (NSLP) and the School Breakfast Program (SBP) are federally assisted meal programs operating in public and nonprofit private schools and residential child care institutions, which provide nutritionally balanced, low-cost or free lunches to children each school day. Participating schools are reimbursed for these meals as long as they meet the federal meal pattern requirements and offer the meals at a free or reduced price for all eligible children. The meal pattern requirements are modeled after “My Plate” guidance and are often some of the “healthiest meals Americans are eating today,” according to Pratt-Heavner.

Offer versus serve (OVS) flexibility is a provision in the NSLP and the SBP that gives students the option to decline some of the food offered in an effort to “reduce food waste and improve menu planning in the school meal programs,” according to USDA’s memo. Schools participating in OVS must offer students a certain number of meal components, and students must select at least three, including fruits and vegetables, as required by the Healthy, Hunger-Free Kids Act of 2010.

Pratt-Heavner says that “over 80% of schools that participate in the NSLP have implemented OVS at lunch,” while that number is “a little bit smaller at breakfast.” She says that OVS flexibility “strikes a nice balance between educating students about what is included in a healthy meal and encouraging them to try those foods, while not making them take every item” in an effort to reduce plate waste.

How can OVS flexibility reduce food waste in school cafeterias?

“OVS is about recognizing that there will be some kids who might not be particularly hungry that day, or maybe they aren’t big milk fans,” says Pratt-Heavner. “Rather than waste an item that the child has already decided not to eat, OVS only mandates that the schools offer all the required items, giving students some choice on whether or not to take all of them.”

According to the memo issued in June, “USDA research has found that the use of OVS is associated with significantly lower levels of plate waste for overall calories, fruits, and vegetables.” While the memo only served to reinforce existing guidance, “it’s great that the USDA put out this clarification emphasizing the importance of OVS,” notes Pratt-Heavner. “Resharing this information and emphasizing the USDA’s commitment to this option and flexibility goes a long way to encouraging schools to take advantage of OVS,” she explains.

This is particularly important in light of past research from World Wildlife Fund’s Food Waste Warriors program that found “substantial policy confusion among administrators, teachers, aides, and cafeteria staff about OVS options and concerns over reimbursement.” Their research suggests that clarity on national guidelines, like what USDA issued in June, is imperative for proper implementation and effective food waste reduction.

Are there any drawbacks to OVS flexibility?

Implementing OVS flexibility can be difficult, particularly when non-school nutrition staff are monitoring meal distribution, such as teachers who oversee breakfast in the classroom. “Programs are at risk of financial penalties if meals aren’t in compliance with regulations, so training around proper implementation of OVS is important,” says Pratt-Heavner. “Most schools are finding a way to make OVS work—for example, some schools serve breakfast from a kiosk in the hallway, where school nutrition staff can monitor what students are taking.”

Another potential concern is that students who would like to take all of the offered meal components might feel uncomfortable or self-conscious about doing so when OVS is adopted, because they’ll be seen as taking too much—though this is only anecdotal at this point.

Finally, Pratt-Heavner points out that OVS only addresses one cause of school plate waste—taking too much—and there are other reasons for food waste in schools. “When we talk about food waste in schools, time to eat is a critical component, and this is out of the control of a school’s nutrition team,” notes Pratt-Heavner. “We need to make sure students have enough time to eat and visit with friends; if they don’t, there will always be food waste.”

For more information on the OVS flexibility, check out these resources from the USDA:

• Policy Memo

• Tip Sheet for School Food Service Managers

• Educational Signage

Want to learn more about effective ways to reduce food waste in schools? Join ReFED and WWF for “From Classroom to Cafeteria: Actions to Reduce School Food Waste” on August 28 at 1 p.m. ET – register today. You can also sign up for ReFED’s mailing list to stay in-the-know on important resources around reducing food waste in schools.