In The Adventures of Tom Sawyer, Tom Sawyer is a lovable rogue. Although he's forever getting into trouble, he's basically a good boy with an understanding of right and wrong. Tom's also a very imaginative young man, who comes up with all kinds of fun new games for himself and Huck to play.

Tom Sawyer is described as crafty, youthful, and heroic. He manipulates others into doing his work, such as whitewashing a fence. His emotional reactions to Becky’s indifference reveal his boyish nature. Despite his mischief, he shows heroism by testifying about Dr. Robinson’s murder, which earns him admiration and respect in his village.

Tom Sawyer wished he was sick to avoid the "slow suffering" of a new school week, which he found particularly miserable after a holiday. He disliked the inactivity and the unkind schoolmaster. Tom tried to feign illness by complaining of a sore toe, but Aunt Polly saw through his ruse. When he mentioned a loose tooth, she pulled it. Ultimately, Tom's attempt to avoid school failed, and he ended up facing punishment for being late.

Tom persuades other boys to do his work by pretending to enjoy whitewashing the fence, making it seem like a rare and desirable opportunity. When his friend Ben passes by, Tom acts absorbed in the task and implies that not everyone gets a chance to paint a fence. This reverse psychology makes the boys eager to try it themselves, leading them to trade their toys for the chance to paint, thus completing Tom's chore for him.

Tom and Joe run away because Tom feels rejected by Becky Thatcher and burdened by the secret of Injun Joe's crime, while Joe feels unloved after being wrongly punished by his mother. They decide to become pirates on Jackson's Island. However, they feel guilty about stealing supplies, realizing it violates biblical commandments against stealing. To ease their conscience, they vow to be pirates who do not steal, allowing them to sleep peacefully.

Tom Sawyer exhibits several negative traits, including mischievousness, manipulation, and selfishness. He cleverly manipulates his peers, as seen in the whitewashing scene where he tricks others into doing his chores. Tom also selfishly seeks recognition, such as when he exchanges treasures for unearned Sunday School tickets, demonstrating his lack of true religious knowledge. His selfishness is further highlighted when he runs away to Jackson's Island, causing distress to his family and friends without concern for their feelings.

When Tom first sees Becky Thatcher, he is immediately captivated and tries to win her admiration by showing off with acrobatic antics. Becky pretends to ignore him but encourages his attention by tossing a pansy over the fence. Later, Tom's feelings are hurt when Aunt Polly wrongly accuses him of breaking a sugar bowl, and he imagines scenes of himself tragically ill or dead to comfort himself, envisioning his aunt's remorse and pleas for forgiveness.

Tom Sawyer is afraid of Aunt Polly, despite his mischievous behavior. She is a formidable figure who uses physical punishment to enforce discipline, as seen when she catches Tom stealing jam. Although she is kind and patient, Tom still tries to avoid being caught by her, indicating his fear. For example, he invents a story to explain his damp hair after swimming instead of attending school.

Tom throws clods of earth at Sid as an act of revenge for Sid revealing to Aunt Polly that Tom played hooky to go swimming. Tom had tried to cover up his absence by resewing his shirt collar with black thread, but Sid noticed the discrepancy with Aunt Polly's original white thread. As a result, Tom was punished with whitewashing the fence. After the task is completed, Tom retaliates against Sid for snitching on him.

Tom Sawyer dislikes school because he sees it as "captivity," particularly resenting Monday mornings after weekends of freedom. His issues include troublemaking, excessive energy, lack of interest in schoolwork, and frequent punishments, such as beatings and ear-pulling by his teacher. Tom struggles to concentrate, preferring activities like chasing girls, fighting, and playing with bugs. Ultimately, he desires freedom to engage in outdoor activities like fishing and swimming, which school prevents.