I read Grapes of Wrath for my AP English class, and it was a struggle to start, but at the end even I was swayed by its mastery. 
 It's very depressing, cruel and harshly realistic about the Dust Bowl and Okalahoman farmers moving to California. California, to look for a new beginning, is their destination. And along the way, it's all about the struggles as humans they go through, their self sacrifices, soul searching and willingness to band together just to get through it alive. 
 If nothing, Grapes of Wrath is moving, and heartbreaking but tedious with description and choke full of lengthy descriptions. I don't recommend this if you absolutely hate historical fiction, as it takes a certain preference of historical fiction to enjoy this novel. I liked it in the end. Maybe it's because I'm a sucker for historical fiction, maybe it's because I was forced to read it, but I enjoyed it. I don't think I could've grasped the symbolic Christian references - and I think it would be much more appreciated by a more worldly, older generation than mine. 
 Regardless, try it. It's a classic anyway, there must be a reason for that. Maybe you'll even like it at the end like me.