These are some of the longer discussion questions I have used in teaching this novel.
-the relationship between George and Lennie.
-the various visions and dreams that comfort the characters in Of Mice and Men.
-the role of foreshadowing in the novel.
-the view of relationships between men in the novel.
-George’s actions at the end of the novel. How can we justify what he does to Lennie? How can we condemn it?
-Steinbeck’s descriptions of the natural world. What role does nature play in the novel’s symbolism?
Some questions from enotes.
Why does George say that migrant workers who travel from farm to farm are the loneliest people in the world?
What dream do George and Lennie share?
What scenes of death does Steinbeck describe in the beginning of Chapter 6 that parallel the events of the previous chapter and foreshadow the event to come?
How does the Chapter 6 bring the book full circle?
Of course, I haven't taken GCSE's, but as a teacher, these are the questions I consider important. I hope these help, and good luck on your tests.