If you’re interested in working in Nicaragua, Nepal, Tanzania then Raleigh International may be worth looking at. They run International Citizen Service (ICS), a volunteering programme which is funded by the UK government. This means your flights, visas, vaccines, training, food, accommodation and travel are all covered. Raleigh International delivers ICS in Nepal, Tanzania and Nicaragua, and they are currently looking for volunteers for 10 weeks next spring.
You need to be 18-25 and a UK citizen or an EU citizen who has lived in the UK for 12 months. Volunteers are asked to fundraise £800 to show their commitment