LitCharts assigns a color and icon to each theme in The Adventures of Tom Sawyer, which you can use to track the themes throughout the work.
Boyhood Rebellion and Growing Up
The Hypocrisy of Adult Society
Superstition, Fantasy, and Escape
Showing Off
Sentimentality and Realism
Summary
Analysis
One day, Tom gets the urge to go hunt for buried treasure. He recruits Huck to help him, who agrees. Tome then explains to Huck that in order to discover treasure they must first find a treasure map by digging around haunted old houses and dead trees. Huck expresses dismay at all of the hard work involved, but Tom responds that great rewards can only be earned through hard word, and convinces Huck to persevere with promises of enormous wealth.
Tom's ideas about how to find buried treasure are ridiculous, and yet at the same time he has begun to express adult ideals such as the belief that hard work is the only way to earn rewards. This combination of absurd superstition with adult ideals does two things: it shows how silly the accepted adult ideals really are, but also shows that, while remaining a kid, Tom is embracing the beliefs of his community.
They set to work digging under a dead tree on the hill by Still-House branch. As they dig, they imagine what they might do with the treasure. Huck would have pie and soda every day and go to as many circuses as possible, spending the money quickly to avoid his father's getting near it. Tom says he would buy a drum, a sword, a necktie, and a puppy, and get married.
In his desire to get married, Tom shows his attachment an idea associated with the stability of adult life. Huck is more attached to his boyhood ideals, and can't relate to Tom's desire to build a family because his own is so dysfunctional.
Huck insists that wives bring unhappiness, and that by getting married Tom will be abandoning him. Tom promises Huck that he can live with Tom and his wife, though Tom keeps his crush on Becky a secret.
Not mentioning Becky suggests that Tom is beginning to break from his boyhood community. Huck's disillusionment with marriage that while Huck is also growing up he does not accept the town's ideals or social norms.
They continue digging, with no success. Eventually Tom realizes the problem is that they need to dig at midnight, under the shadow of a dead tree limb. They plan to meet again that night.
When experience contradicts what Tom desires, he rewrites the rules of his fantasy world. He lacks a realistic sense of the world, which would bring a quick end to his fun.
After nightfall, they start digging, again with no success. Huck is scared that witches and ghosts might be watching. Tom suggests they dig in yet another place: the haunted house. They agree to dig there the following morning, when Tom says the ghosts will be away.
Tom's ideals and sense of romantic adventure make him willing to do things that the more realistic Huck is not. In other words, in many ways, it is Tom's lack of realism that makes Tom such a powerful leader.