Greg and his father are talking about his grades. He is concerned about his grades, and this shows that he wants his son to succeeed.
Greg wants to play basketball, but his father says that he has to focus on his math grade rather than a sport.
Greg felt as though no one understood him, so he ran off. His father had only wanted him to succeed with his grades.
Greg found himself in an old house, which he thought was vaccant, but it was occupied by an old man, Lemon Brown, who eventually helped him to agree with his father.
After the old man and Greg are talking for a while, three men broke into the house looking for Lemon Brown's 'treasure' that they had overheard him talking about. With Lemon Brown being a father fugure, it helped Greg understand his father's point of veiw.
Lemon Brown showed Greg his so called 'treasure', the treasure being an old harmonica and some newspaper clippings. Greg then understood how what some consider trash, others may cherish.