This is an interesting question, because, due to the changes that the character of Holling Hoodhood goes through in the course of the narrative, the adjectives that would best describe him change from the beginning to the end of the book. In the opening chapters, Holling might be described as passive, self-absorbed, and paranoid. By the end of the narrative, however, his character has matured, and he might best be described as caring, courageous, and perceptive.
In the beginning of the book, Holling is mostly an observer, and the recipient of things that happen to him. He is worried about being the only one left in class on Wednesdays, but cannot do anything about it. He does bring his concerns home to his parents and sister, but when they do not offer any constructive help, he once again is left helpless. Holling is passive at this point, with no idea how to take charge of things and take control of his life.
Holling also shows himself to be self-absorbed and imaginative in his reactions to Mrs. Baker. Holling has become convinced that Mrs. Baker is out to get him, and interprets her every action as part of a ploy to do him in. In his complete self-absorption, he imagines that Mrs. Baker is hatching fantastic plots to hasten his demise, and never even considers that she is an individual in her own right, and that some of her actions might be a reflection of challenges she herself is facing in her life.
By the end of the story, Holling has changed considerably. He is able to see things from the viewpoints of others, and has learned to appreciate people as individuals, and to value the communion he shares with them. Holling is caring, in that he is able to empathize with his sister in her search to find herself, and puts himself out to help her when her cross-country venture goes awry. He is perceptive, as shown when he is able to see the underlying meaning and value in his friend Danny Hupfer's bar mitzvah, and is courageous, as he demonstrates by standing up to his father when his father belittles Danny's ceremony as well as his, Holling's, aspirations for his own life. Through his development during his seventh-grade year, Holling has progressed from being passive, self-absorbed, and paranoid. He is now aware of the needs of others, and knows the value of taking control of his own life, courageously shouldering responsibility for his own destiny.