Tom goes to the accepted and respectable school, attends Sunday school, and is invited to parties in other people's homes. Huck does not attend school and, naturally, is not invited to parties. Instead he is free from responsibility and moves freely in and out of the town, sometimes disappearing for days, and is never missed. His education is from the proverbial "school of hard knocks."
In contrast to Tom, Huck is an outcast from society. Rather than conform, Huck thrives on his freedom from such restraints as society imposes. He cannot abide by the strictures of living in a regular household where there is no smoking and no cussing and where he must wear proper clothes, keep decent hours, and conform to proper manners, especially table manners. Whereas Tom's life is bound by society, by rules, and by acceptable behavior, Huck's life is one of freedom; he can come and go as he pleases.
This difference between Tom and Huck is seen on Jackson's Island. The first day on the island is one of the glorious days in their lives, one lived to the fullest. But at night time, Tom and Joe, who have basically the same upbringing, have guilty consciences over stealing food for the outing, and even though they say their bedtime prayers--something Huck doesn't bother with--their consciences will not let them get to sleep. In contrast, Huck Finn has no pangs of conscience. He feels no qualms about having lifted (stolen) or borrowed certain items; he feels no compunction to live by the rules of society that has made him the outcast that he is. In fact, Huck has had a marvelous day because he is getting more to eat that he usually gets in the village.
