What does it take to change the world? For a group of five British International School of Boston (BISB) students, it takes 20 hours on a plane, two weeks in Tanzania, and $16,000. The students and two teachers from the Jamaica Plain school will be traveling to the African country in February, working to repair and renovate a primary school and to bring sustainable farming practices to the remote Maasai village, Ensare Sero. Leading up to their departure, the high school students will be hard at work raising the funds they need to support their service work abroad. “Education is really the foundation for a strong society,” said BISB student Teal Fechtor-Pradines, who is part of the service trip.