This teaching unit is based on primary sources taken from documents, artifacts, journals, diaries, newspapers, and literature from the U.S. historical period under study, the end of Reconstruction and the search for an overseas empire at the end of the 19th century. The unit is also intended to introduce students to the medium of the World's Fair, an institution that millions relied on to understand the world and their place in it. According to the unit, the student, by studying a crucial period in history, becomes aware that choices had to be made by real human beings, that those decisions were the result of specific factors, and that the decisions set in motion a series of historical consequences. Within the unit are the following: (1) unit overview; (2) correlation to the National Standards for United States History; (3) unit objectives; (4) teacher background materials; and (4) lesson plans with student resources. The unit's four lesson plans include a variety of ideas and approaches for the teacher that can be elaborated upon or shortened. The unit is designed as a supplement to the customary course materials, and it can be adapted to a slightly higher or lower ability levels. (BT)