Pedophilia means that an adult wants to have sexual intercourse or perform other sex acts with children.
In most countries it is illegal to have sex with someone under sixteen. It is classed as abuse and can be punishable with a prison sentence. A child who has been sexually abused can suffer lifelong problems. If you hear of an adult sexually abusing a child you must report it to the child protection agency or police. The school nurse can help you do this.