Geared to the needs of high school and undergraduate students, this guide presents 500 term paper ideas and print and nonprint sources on 20th-century U.S. history. Entries on 100 of the most important topics, issues, and developments in U.S. history, beginning with the Spanish-American War, are organized in chronological order. Each entry consists of a short description of the topic, followed by five specific suggestions for term papers about the topic, and an annotated bibliography of 15-35 sources appropriate for student research. The annotated bibliography is organized under seven possible categories: reference sources, general sources, specialized sources, biographical sources, periodical articles, audiovisual sources, and World Wide Web sources. An index is included. (AEF)