A funny thing at school

I teach four and five year old's at a preschool. This little boy is always having me smell stuff like empty pringle cans, dandelions, and other normal stuff. Today we were sitting down in the quiet area when he says smell my hand, he was just dropped off not too long ago so I'm thinking lotion. I smell his hand it smells awful and I ask him what that is and he says that's what my bottom smells like. I told him to go wash his hand using lots and lots of soap and water. He couldn't stop laughing; at the time I did not find this humorous.Where else in the job field can you experience stuff like this.