alt Hacker NewsYou described my experience almost exactly. The first time I went to Tanzania I stayed for 2 months and part of that time was in Dar es Salaam in an Airbnb with a small family just outside of Kariakoo, the main market of the town. I also spent time with the family's parents in Kigogo, a densely populated area just outside the city limits that would be considered a slum by most people. The rest of the time was in the village.
I'm curious if you think a documentary could have a similar effect. I'm an amateur filmmaker by hobby and I've been thinking of filming a "Cinema Vérité" type documentary showing the humanity of Tanzania and trying to relate it to life in the US. I think it could be powerful but difficult to get right. I'd love to hear what you think about that.
I am a strong believer that nothing beats personal experience. High school children should do an exchange year in a foreign country. Students should do an internship in a foreign company (IAESTE, AIESEC and a few others). If neither options are available, spend a few months of your summer break in a foreign country, trying to get to local life as close as possible. Come with an open mind and leave with an inspiration to contribute to the betterment of the world.
A documentary can't have anywhere near that effect, it could however motivate more people to investigate and maybe get some people to travel. It also would support the legitimacy of your project. Since if already fits with the things that you like to do, I'd say, go do it. As I wrote in another comment, we should try to find a way to contribute that is most suitable for each of us. And we should make use of all the skills available to us to further our goals. If documentary making is in your set of skills and interests, then by all means.