What do I do with old drapes?

salvation Army would love them especially after Irma

Donate them or better yet Dump them in a thing called trash.

If they aren't in bad condition donate them. If they are not in good enough condition to donate you can use them as drop cloths. If the fabric is thick upholstery grade and some of it is in good condition but not all save the good parts you could make seat cushions, pillows, etc. If you don't sew and don't need a drop cloth or the fabric is good but not everywhere save the good parts and see if there is a place that could use it. Senior centers, even some donation centers will take fabric but they don't want to have to salvage it from a curtain.

My mom cut hers into strips, braided the strips and sewed a rag rug.

Donate them. List on Craigslist. Offer on eBay.

If still in good shape you can donate. Or save to use for future projects.

What kind of fabric is it? I have made throw pillows for sofa/bed, made cafe curtains for another room, made duvet covers from them and a sheet, used the fabric on picture mats using spray adhesive, made cat pillows, anything you need a big piece of fabric.