Novels
Fred and George are introduced in Harry Potter and the Philosopher's Stone (1997) when they meet Harry Potter at King's Cross station. They are two years ahead of Harry, Ron, and Hermione Granger. They are the school clowns and troublemakers, more interested in inventing new pranks than studying. Despite their unimpressive academic record, they show a high degree of knowledge and skill in creating magical jokes and tricks. Both play as Beaters on the Gryffindor Quidditch team and are very talented players.
Fred and George care little for Prefects or rules, which contributes in their eventual falling out with their older brother Percy. Their appearances and personalities are so indistinguishable that they can fool even their mother. Fred appears slightly more aggressive/take-charge than George, which is most apparent in Harry Potter and the Goblet of Fire where George is more cautious about blackmailing Ludo Bagman and, unlike Fred, is not mentioned as having a date at the Yule Ball.
In Harry Potter and the Goblet of Fire, Fred and George begin selling their own jokes by owl order, under the name "Weasleys' Wizard Wheezes."
One of their primary ambitions is to run their own joke shop. Harry makes this possible by giving them his winnings from the Triwizard Tournament. In return, in Harry Potter and the Half-Blood Prince, they allow Harry to take anything from their joke shop for free while asking Ron to pay for the items in his arms.
The pair provide Harry with useful assistance throughout the series; in Harry Potter and the Chamber of Secrets they and Ron help him escape his house arrest at Privet Drive. In Harry Potter and the Prisoner of Azkaban they give him the Marauder's Map. In Goblet of Fire, they try to encourage Harry and Ron to find dates to the Yule Ball by letting them see Fred ask Angelina Johnson. They also help Harry in Order of the Phoenix when Harry wishes to talk with his godfather, Sirius Black, by creating a distraction, leaving Hogwarts in a state of chaos. They were also members of Dumbledore's Army, a group started by Harry, Ron, and Hermione to teach practical instruction in Defence Against the Dark Arts, which Umbridge had removed from that course's curriculum.
Later that year, they are banned from Quidditch and decide to abandon formal education; before leaving, though, they pay tribute to Dumbledore by waging a prank war against the dictatorial Dolores Umbridge.
It is stated by several characters, including Professor Flitwick and Hermione, that despite their poor grades, the Weasley twins are extremely proficient wizards, capable of sophisticated magic. This is evidenced by the large number of inventions they have created and by Fred's ability to transform Ron's teddy bear into a spider even before he was old enough to attend Hogwarts.
