For anyone even more skeptical of where your money goes when you donate to a nonprofit, there are plenty of resources out there for researching this. CharityNavigator is a popular one, but I donate primarily to GiveWell: https://www.givewell.org
But which is more trustworthy? We need a charity watcher-watcher to tell us.
you beat me to it (_/\_)
I worked with a large number of these so called "legitimate" charities and after what I saw I will never give a penny to any non-profit. You will have far, far more impact figuring out something you care about and directly spending $100 to accomplish that than giving $5000 to any of these organizations.
I use watsi.org since its been reliably vouched for on HN for a long time now