Various schools and volunteer programs offer courses ranging from Beginners Swahili to Economic Development. Dar es Salaam also has a well-established University, which has exchange programs with several universities in the US and other countries.
National Parks
There are loads of National Parks for those wanting to watch Tanzania's wildlife. You can gain entry for around $100 US and benefit from a tour and perhaps a night's accommodation. The better parks, though packed with tourists, are found in the north of the country. Ruaha National Park is the best in the south locals actually say this is the best park, especially if you want to see wild animals as opposed to semi-tame ones in the northern parks. Don't just be sucked into the tourist circuit in the north; the south offers great parks and towns base yourself out of Iringa, and you will feel less of a tourist and more of a guest if you travel this way.
Scuba diving
In and around pemba and zanzibar is another good experience.
Slave Trade sites
You can also visit numerous historical Slave Trade sites, which could make for an interesting, if a little depressing, excursion.
Beaches
Did you know that tanzania has some of the best, most unspoiled beaches in the world? they are stunning, with their white sand, palm trees, and cool indian ocean water!
Kayak the beautiful coastal waters with a tour operator.
Stone Age sites
Tanzania has two of the best Stone Age sites in the world: Isimila Gorge near Iringa and the earliest known examples of human art among the rock paintings, near Kolo, north of Dodoma -- some of which are reckoned to be around 30,000 years old.
Kilimanjaro
Is one of tanzania's main attractions. kilimanjaro is the highest mountain in africa. many visitors come to tanzania to summit this great mountain. the main peak is estimated to be 5895m high making it a real challenge for mountaineers.
There is a wide assortment of volunteer organisations sending volunteers and interns to Tanzania to do work in health care, orphanages, education, and development projects. Finding a paying job may be more of a daunting task, taking more time and making use of local connections, but a job could be certainly obtainable when sought hard enough.