When the school master had seen that his book was torn, he immediatley scanned his classroom to look for a guilty face.  Tom knew that Becky had torn it, and did not wish to see her whipped.  Tom wanted to say that he did it and take Becky's punishment for her.  And that is just what he did.  Tom yelled out loud that it was him that had torn the book, and he recieved a whipping for it.  He then had to stay after school for a couple of hours.  Afterwards, he left the school and sure enough, Becky was out side waiting for him.  She complimented him for being so "noble".  It was getting towards the end of school now, and I guess every year, before school ends, the school has examinations.  This is where the parents and other family members of the students come to the school and listen to each student recite something that they had learned that year.  Also during this time, a group of boys, including Tom Sawyer, were trying to think of some way that they could get revenge on their schoolmaster for he cruelty that he showed against them.  On the day of the examinations, each student got up and recited things.  Tom tried to, but was overcome with stage-fright, and was not able to finish his speech.  After these were all done, the teacher stood up to go and draw a map the U.S. on the blackboard so that the students could show all of the geography that they had learned that hear.  Now, I did'nt totally understand this part, but what I got from it was that the boys that wanted to get revnge on the teacher ended up going through with their plan.  What they did was get a cat and tie him to a string.  Then they somehow lowered it from the ceiling.  Now, of course the cat is way scared, so he is going to try and grab onto anything that he can get his paws on.  Well the boys knew this and so they lowered the cat near the teacher's head, and the cat attempted to grab for his head, but only caught hold of his wig.  Then the boys pulled the cat back up.