why does Crooks want to be a part of the farm that Candy, Lennie, and George want to buy? What might the farm symbolize to him?

Crooks is a misfit on account on his colour and his back. He is initially excited because the farm would be a place where he wouldn't be alone. It would be a place that he would feel wanted, the farm would give him a dignity he never had.

He wants to be a part of the farm because he wants to be a part of something....

"A guys goes nuts if he ain't got nobody. Don't make no difference who the guy is, long's he with you...I tell ya... a guy gets too lonely an' he gets sick"

Being a part of the farm would mean Crooks wouldn't be alone.