The story of lunch exchange in Crayon Shinchan happened in episode 142 of the first season. In this episode, Xiao Xin likes to have lunch with his friends in the kindergarten. Usually, Xiao Xin's lunch is carefully prepared by his mother Meiya, but on this day, Xiao Xin is tired of his lunch and is eager to try someone else's lunch. So, he put forward the idea of exchanging lunch boxes, which was positively responded by other children. Everyone exchanged their lunch boxes with Xiao Xin.

During the lunch exchange, Xiao Xin tasted all kinds of delicious food, including sushi, fried chicken and cakes, which made him feast his eyes. However, when he ate his last friend's lunch, he found that it was a healthy lunch full of vegetables, which made him lament his choice.

This episode shows the friendship and interaction between Xiao Xin and his friends by exchanging lunch boxes, and also conveys the concept of cherishing food and not being picky about food.