Thank you for all your great suggestions. The bag of yarn seemed to have jumped ship on it's own. My neighbour saw my mom bringing in that giant bag of yarn, and asked me about it when I was bringing out the trash. Turns out she crochets, and does alot of volunteer work at an old age home, since her husband is there. She said they'd be happy to have it, so she took it.
That worked out alot better than I could have hoped. As I DO NOT drive, so bringing it out to donate would have been really difficult.
Thank you again for the ideas.