Ngobi, Francis. The effect of instructional materials on the performance of students in Geography at "O" level in Buzaaya County, Kamuli District / Fran cis Ngobi. - Kampala, 2001. - ix,29p. : tabs ; 30cm. Dissertation (B.Ed.) - Makerere University , 2001. Includes bibliographical references (p.29). Subjects--Topical Terms: Teaching --Aids and devices.------