It was the first of her two stops in Mississippi, which ranks No. 1 in childhood and adult obesity, according to the Centers for Disease Control and Prevention.
The first lady's visit was part of her recently announced Let's Move! campaign to promote school healthy habits at schools.
Maggie Benson White, who was putting up a poster outside Pecan Elementary School to welcome Mrs. Obama, said she hoped that the first lady's visit would inspire healthy eating habits in her community and at inner-city schools.
"Our children are not eating properly. We have a lot of parents who don't know how to serve nutritious meals. If we could teach them to let McDonald's go, it would have a big impact," said White, who is president of the West Park Neighborhood Association, where Pecan Park Elementary is located.
Mrs. Obama was joined at Pecan Elementary School by Mississippi Gov. Haley Barbour and his wife, Marsha. School principal Wanda Quon told Mrs. Obama that the playground equipment was paid for with grants.
The first lady's campaign on obesity has four parts: helping parents make better food choices, serving healthier food in school vending machines and lunch lines, making healthy food more available and affordable, and encouraging children to exercise more.
On her second stop, during a discussion with several state and local school officials at Brinkley Middle School, Obama said she came to Mississippi to "highlight" the strides the state has been making in addressing obesity.
The Mississippi Department of Education has started several programs to increase physical activity at schools, boost the consumption of fruit and vegetables in lunchrooms and reduce fried foods on school menus.
Obama said she realized its difficult for some schools across the country to make those type changes immediately because of funding issues. She said the Child Nutrition Act that is up for reauthorization includes $10 billion to help with those issues.
The Centers for Disease Control and Prevention has long said that nearly a third of Americans are obese. In 2009, Mississippi had the highest rate of adult obesity, 32.5 percent, for the fifth year in a row.
Mississippi also had the highest rate of overweight and obese children, at 44.4 percent in total, according to the CDC. It's followed by Arkansas, 37.5 percent; and Georgia, 37.3 percent.
Mrs. Obama did not take any questions while at the school. Before leaving, she crossed the street to talk to about two dozen people gathered outside.
Aides said Mrs. Obama chose Pecan Park Elementary because the school has taken several steps to encourage students to be more physically activity. The school's walking trial was completed in 2007 and it added a playground and cardiovascular workstations.
Read more Parenting Perspective blogs by visiting the Parenting Channel on 6abc.com.