The two best donate your car charity organizations are Karsforkids and Habitat for Humanity.
Both those are two great very legit charities that accept cars as a donation and they then either sell them for scrap metal or they sell them for a profit to someone and use the proceeds for funding their organization.
Besides those two there are also other car donation charities such as V-DAC, One Car One Difference, The Arc Vehicle Donation, Allstate vehicle donations.
Those are all some good legit organizations to donate your car too.
When you do donate your car to a charity and you're unsure if the charity is legit just do some research on the charity and check for reviews.
But the above organizations or legit car donation organizations and you can sometimes get an income tax deduction when donating your car to charity.