I think it will be memorable in many levels, self growth, independence, new friends, resilience, patience, gaining values, learning new cultures, cooperation, solidarity ...
I think it gave him a very different and healthy perspective on what the world is like outside the Bay Area bubble and other tourist destinations he's visited. I also think he felt good about helping others in need, which will hopefully be a feeling he'll remember and will want to experience repeatedly in life.
Our son has come home with a new awareness about the difference one can make in the lives of others. He has gained skills & confidence from working on the projects in South Africa & most importantly he has made new friends on the other side of the globe.
His understanding of and willingness to work to understand the issues in other cultures and places has been ignited by the trip. The opportunity to form friendships with people in other countries/cultures was life-changing.
It is very important for young people to experience that not everyone has easy access to even basic things like quality food and health care that we may take for granted, and to opportunities that enrich their lives one way or another. Also, it is important to experience that one can help others, less fortunate, in any way possible and that helping makes oneself really happy - more than any material thing could.
Hopefully my child will recognize his level of privilege, that what he experienced also happens in the US, be empathetic to those less fortunate than he, and be willing to work towards a common good for humanity.
My daughter felt compelled by the friendliness and happiness shown by the locals. She was positively surprised on how much one can do with so little. Last but not least, we, the parents, think that this trip had a positive impact not only to open her eyes to the reality of this world but also to take her first steps towards independence, preparing her better for the big separation from her family that is soon coming up when she goes to college.