Okay, before I show you what I got, I want to say a few things.
First of all, when thinking about what kind of logo I should do for your site I came to the conclusion that there are basically just 2 style directions in which you could go that fit, with the first one being a very friendly more hand-drawn like style, simply because I think it's quite common for charity organizations and it fits.
But I decided to go with the second style that's also typical for charity organizations and that's a more serious, business like style. When donating for a charity organization, people want to know that their money is in good hands and really gets used for the way it's supposed to be. A more serious logo supports that image and because of that I think it's the best choice.
Furthermore I think that the basic concept of your current logo is pretty good it just lacks the right execution. So I sticked very close to the current logo with this one, I will explain more about that later.
Also to contribute to the more serious style I think it's better to stick to a max of 3 colours. At the moment my logo is black and white, but that's because it's just the concept. I wanted to make sure it looks alright in black and white before choosing colours. If you prefer a mono-coloured logo, we can keep it that way too of course.
I haven't done the type yet, so it's just the symbol atm.
http://s2.directupload.net/file/d/1499/9ahxrmak_gif.htm
As you can see the symbol still has the sun (I can delete the lightrays if you don't like them, not sure about them atm), but instead of one "avenue" there are two. This has two reasons. First of all, by going out of the circle the two avenues also build an "
A" standing for
Another
Avenue.
Also the two roads are running into one point at the horizon. That's first of all to put in in a correct perspective, but it also has a symbolic character: The first avenue could symbolize the world we live in and the second could stand for the "Third World". As both avenues are running together at the horizont it shows that we can live in one world in the future.
So, that's it.

I first want to make a fitting logo before even starting with the webdesign. I think it's mor eimportant to get a fitting logo first and then build the site based on that logo.