I noticed most of the comments say to donate it.
I do not know your situation, or why you are with you son... but if you are in need of cash, there is nothing wrong with sorting through it, keeping what you think you will want or need, and selling the rest of... be it on the net or at a flea market, yard sale, etc.
If you do not take it, what does she plan to do with it? If she is planning to just toss it, then yes, by all means, take it. You will have a better idea of what is worth keeping and what is considered trash.