The national Amigos de las Americas program lets you volunteer to do public health work in Latin America during the summer. Your Spanish teacher can probably tell you more about it. http://amigosinternational.org/
Through United World Colleges you can attend an elite private high school in New Mexico, Canada, Norway, Wales, Italy, Venezuela, India, Africa, Hong Kong or Singapore – and it’s free! You will end up going to high school for an extra year, but these high schools look and feel more like college. Besides, you will earn an International Baccalaureate diploma, which will look good when it’s time to apply to a 4-year university. http://www.uwc.org/
National Federation of Temple Youth-Eisendrath International Experience High School in Israel: http://www.nftyeie.org/
Congregation Rodef Sholom, the synagogue in our area, has a month-long summer program in Israel for teens that focuses on Judaism and Israeli-Arab coexistence. Probably other major synagogues have something like this too. http://www.rodefsholom.org/learning/teens/572-lets-go-israel
AFS Intercultural Programs http://www.afs.org/
Edu-Culture Immersion http://educulture.com/Programs/
The Experiment in International Living http://www.experiment.org/
American Youth Leadership Program (run by the US Department of State) sends high school students 15-17 to foreign countries for homestays and service projects. http://exchanges.state.gov/us/program/american-youth-leadership-program
Over the years a few of our students have arranged their own informal high school semester abroad by going to live with a close family friend or relative (like an uncle or aunt) who happens to live overseas in places like England or Germany. They just enrolled in the local school and didn’t worry too much about whether it might disrupt their education. One of these went to Australia for a whole year to live with his uncle. He said the Australian school he went to wasn’t as good as ours but it was worth it anyway. When he returned his peers voted him onto the homecoming court, so at least the year’s absence didn’t hold him back socially. He graduated with the rest of his class and went to college in the States.