I have found that a person's lifestyle often decides what charities they find appropriate for themselves.
My personal choices are:
Habitat for Humanity. They are a world wide organization that helps people to own their own home and during the process the family actually are required to participate in any way they can. It is often after they have worked over 250 hours that they even get to know what home/homes are in their possible future. They work in any way they can on any number of homes, our local chapter can have anywhere from 3-10 houses being rehabbed at any given time because people are always leaving us their homes when they pass on. They have also left us parts of their fortunes along with other charities. So when a family is working the organization may be working on several different homes in different parts of the City and there may be several families ahead of them. BUT the next available home may not be where the next family in line wants to live or have their kids go to school....so that home may be up for the next person to choose from.
Habitat can be asked to keep all the money in your local area or it can be ear tagged to go overseas, or even spread out equally to both.
Another charity that I support is Big Brothers/Big Sisters. There isn't one in my local town so I do support the one in my old college town. They really try to make sure the kids are safe and that they put kids with Bigs that have similar interests so that they actually get to do stuff during their time together that is fun.
I think that if you call around you can find local charities such as food banks, churches that provide Christmas gifts to kids, other organizations that will have some sort of local community impact. I would rather give to those than to some huge organization that spends over 50% of it's income on salaries, although those agencies to need staff they also are much larger that your local agencies/community organizations.
Salvation Army and Community Action are both community organizations that could really use some cash to help with their Christmas programs.
You can always go to child welfare or some other state agency too and ask them if they have a worth family that could use a holiday sponsor. My daughter was selected as one local department stores family and they took donations in November and December. They paid off all her traffic fines, got her license reinstated, someone donated a small family style car and they tagged it and insured it for 6 months, she got used furniture donated, the kids nearly got whole new wardrobes, some used and some new, she got 3 TV's that people didn't need anymore, she got her kitchen cabinets filled with donated canned goods, etc.....she was just getting out of rehab and was doing really well. She is still doing well and this support was something totally unexpected. She didn't think she would ever get her traffic fines paid off. For someone who has no income $600 is the same as our national deficit...no chance of ever being paid.
If you think about it and do some local research I think you will find some organization or family that is worthy. Even your local school might be able to guide you to find someone.