From Chapter 1, some possible questions would be:
- Why was Buck such a valuable dog at this time and place (he was big and strong, gold was discovered in Alaska and people needed that kind of dog...)
- What was so important about the man in the red sweater?
- Why was the man's club a "revelation" to Buck?
From Chapter 2, you could ask
- What are two reasons why Curly's death was important for Buck's education and his future?
- What makes Francois think Buck is so smart?
- Why did Buck stealing bacon show that he was "fit to survive?"