To be able to work in Suriname, it is necessary to apply for a working visa. Tourist visas do not permit legal work, but of course, volunteering is an option.
If you manage to get a working visa, a solid work option is teaching English. Even better if you arrive in possession of a TEFL qualification as you will be in a better position to demand decent working conditions. However, English teachers are in such high demand that even without the TEFL qualification, it shouldn’t be a problem to find work. Work is readily available in private language institutions, public schools and also within companies.
Volunteering work is a great thing to do if you really want to spend some time in the country and also want to access areas and situations that are not common to the regular tourist route. Many volunteer projects require you to raise a large sum of money in sponsorship and for this reason it is worth researching this in great depth and well in advance if you are considering it as a serious option.