We volunteer to help out with the various ongoing projects run by the CWWC (Christian Women's Works of Charity). So, you could spend time at the main center, which is mostly crowd entertainment and control, of the pre-K sort. You could walk up to Gataka, which takes about 30 min, and is a similar sort of place. It's good to know what the CWWC does. Or you could hang out in one of the local medical clinics, which is always cool. They are not affiliated with the CWWC, but they always appreciate the help, and you see a lot. It's a very safe, friendly slum/rural area. The work is rather intense, and the weather can be, too, so you mostly knock off around mid-afternoon.
But let's face it, we are all unskilled labor. And they have plenty of that already. So what we can offer is money, to be blunt. It's easy for us to part with, and easy for us to get. For $15 you can get a young HIV-positive mother a school uniform so her little girl can go to school for a year. And you meet with her, and hear her story, and give her some dignity and concern. We call them home visits.
Best idea of all is to raise money and try to establish something sustainable. What I've been thinking about for a while now is sewing machines. If we could get 5-10 of them, the good ones, we have a room for them, and the women could learn how to use them and make stuff for sale, and stuff for use, like school uniforms. I ask my students to raise $3-500 apiece, and they do a lot with that money, a whole lot.
The family we stay with is super cool, very warm, very politically aware. The best group of people you'll ever meet. Room and board is $10/day, and you get pretty nice accommodations: electricity, hot water that you heat up on the main fire, likely a room to yourself. And the food, let me reiterate, is good vegetarian, if you ask for it. If you travel some, you can get south-indian food, and also you can see traces of it in the more local fare.
They have good connections at the airport---the father worked there for 35 years--so it's an easy trip in and out, and a short car ride to their place. The oldest son works in the tourist industry, and takes people on safari. Everyone raves about him and his tours, but I've never been. It's about $100/day. Nairobi--a truly godforsaken place--is about 30 minutes away by public transport.
I also have a very good contact in Nyeri, to the northwest. It is a much wetter, jungle-like rural atmosphere, and Nancy is a wonderful social worker who will show you everything. Travel is not a great idea these days, but the family is from Nyeri, and go there a lot, and so know if the route is safe.