How do the children get rid of hagrids dragon?

In "Harry Potter and the Sorcerer's Stone," Harry, Ron, and Hermione help Hagrid with his dragon, Norbert, by arranging for him to be smuggled out of Hogwarts. They enlist the help of Charlie Weasley, who works with dragons in Romania, to take Norbert off their hands. The trio manages to sneak the dragon out of the castle and into the hands of Charlie's friends, effectively getting rid of Hagrid's unwanted pet. This helps protect both Hagrid and the students from the dangers associated with keeping a dragon at Hogwarts.