Been there, done that. (As a student) I wanted to more experience so I did what you're doing for a while.
Here are some pieces of advice I can give you:
- Shared hosting is always a good option (cheap, auto-updates, no hassle, and everything via a web-panel (typically c-panel)
- Make sure all the hosting and domain names are always in their name. (You don't want to be bothered a year later to renew something)
- WordPress is the way to go.
- Make sure you have an exit strategy for every project (When do you get off) most NGOs will try to get you working as long as possible as IT support, it can take a lot of your time.
To take you up on your offer, just one question : Do they have to be US based or anywhere in the world ?