Uganda has a variety of landscapes which most tourists find interesting. The North is relatively flat and dry savanna while the East is mountainous and lush and the centre of Uganda hosts larges forests.
The national parks are beautiful and, on the whole, uncrowded. See the Uganda Wildlife Authority UWA website (http://www.uwa.or.ug/) or for details of gorilla tracking, safaris, chimpanzee tracking and more. Prices in several parks seem to be set at 20 1 day, 35 2 days. An ISIC student card cuts you a 25% off the entrance fees these days.