When writing a book report, consult the teacher's requirements first. If the report is simply to summarize the reading, then focus on the main points of the story that move the plot forward. If, on the other hand, the assignment is to compare and contrast characters, show cause and effect, or argue a point, then your report will be structurally different.
For The Pigman, though, show how the interaction between John, Lorraine, and Mr. Pignati developed into a loving and respectful friendship. Then, consider what obstacles their friendship faces as the story progresses and identify the climax and resolution. Create a thesis statement that will drive your essay forward towards the main point of the essay. For example, a thesis statement could be: "John and Lorraine learn that not all adults are difficult to be with as Mr. Pignati laughs with them, gives them gifts, and creates a safe environment for them."
The next step after creating a thesis is to structure your paragraphs to explain and support it. In the above example, there are three items to address in your essay that could also be topics for three different paragraphs. Remember to provide quotes with citations for each topic addressed because this solidifies your main idea and thesis statement.
Don't forget to provide a strong conclusion that elaborates on why your topics and thesis are important to understanding the book. Discuss how the book can help to address social issues for teenagers based on the topics you mention. The following are quotes that could go with the topics given in the above thesis statement example:
He laughs with them:
"We must have looked just like three monkeys. The Pigman, John, and me--three funny little monkeys" (97).
He gives them gifts:
"'I don't want you spending all that money, Mr. Pignati,' I said.
'Nonsense,' he insisted.
But I really didn't. And still it felt good. No one had ever bought me stuff like this before--something I just liked and didn't need and didn't even ask for" (90).
He provides safety:
"Lots of times I'd cry myself to sleep, but more and more I felt myself thinking of the Pigman whenever I felt sad. Sometimes just after I put the light out, I'd see his face smiling or his eyes gleaming as he offered me the snails--some little happy detail I thought I had forgotten--and I'd wish my mother were more like him. I'd wish she knew how to have a little fun for a change" (86).