In 1792, recent college graduate Eli Whitney moved to Georgia to work as a tutor on a plantation. There, Whitney learned that southern planters were eager to make cotton a profitable crop. Once cotton was picked from the field, seeds had to be removed from the cotton fiber by hand before cotton could be sold. This process was labor-intensive and time-consuming, and it limited the amount of cotton that planters, relying on the work of enslaved people, could produce.

This collection uses primary sources to explore the creation of the US Constitution. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to explore cross-cultural conflicts during the Colonial period of US History. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to explore Arthur Miller's The Crucible. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

At the end of a six-year armed conflict called the Cuban Revolution, Fidel Castro’s 26th of July Movement ousted Cuban President Fulgencio Batista on January 1, 1959, and ushered in a new government. Within months, as Castro began to implement policies and align with the communist Soviet Union, hundreds of thousands fled Cuba for the United States. Most were educated members of the upper and middle classes. Many of these immigrants, termed “exiles” and “refugees,” believed their stay in the United States was temporary because Castro’s government would be short-lived. As Castro’s regime persisted, they realized their flight could be permanent. Pushed out by the consequences of the Revolution, the influx of refugees swelled the Cuban population of the United States from 79,000 in 1960 to 439,000 by 1970. Cubans settled across the country, with the most significant community in Miami, Florida, followed by Union City, New Jersey.

This collection uses primary sources to explore the Declaration of the Rights of Man and of the Citizen. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to explore early Chinese immigration to the United States. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to explore the introduction of electric power to the United States. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to environmental preservation in the Progressive Era. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to explore the Equal Rights Amendment. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

In 1883, Sir Francis Galton, a nineteenth-century English social scientist, statistician, and psychologist, coined the term “eugenics” from the Greek word eugenes, meaning well-born. The practice of eugenics aims to improve the genetic quality of a human population through selective breeding—encouraging reproduction for the “strongest” humans while discouraging reproduction for the “weakest” humans. Cultural, social, and scientific ideas of the late nineteenth-century informed how eugenicists identified desirable and undesirable genetic traits. According to these eugenicists, the “strongest” humans were typically white (from northern and western Europe), healthy, and wealthy. The “weakest” humans were typically non-white (or white from southern and eastern Europe), poor, physically or mentally disabled, or considered criminally or sexually “deviant.”

This collection uses primary sources to explore early exploration of the Americas. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

Alternative facts, fake news, and post-truth have become common terms in the contemporary news industry. Today, social media platforms allow sensational news to “go viral,” crowdsourced news from ordinary people to compete with professional reporting, and public figures in offices as high as the US presidency to bypass established media outlets when sharing news. However, dramatic reporting in daily news coverage predates the smartphone and tablet by over a century. In the late nineteenth century, the news media war between Joseph Pulitzer’s New York World and William Randolph Hearst’s New York Journal resulted in the rise of yellow journalism, as each newspaper used sensationalism and manipulated facts to increase sales and attract readers.

This collection uses primary sources to explore Fannie Lou Hamer and the civil rights movement in rural Mississippi. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to the history of food stamp programs. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to explore the Fifteenth Amendment. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to explore The Fire Next Time by James Baldwin. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to compare and explore the relationships between Frederick Douglass and Abraham Lincoln. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to explore the history, successes, and failures of the Freedmen's Bureau during Reconstruction. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.

This collection uses primary sources to explore the steam engine and transportation in the nineteenth century. Digital Public Library of America Primary Source Sets are designed to help students develop their critical thinking skills and draw diverse material from libraries, archives, and museums across the United States. Each set includes an overview, ten to fifteen primary sources, links to related resources, and a teaching guide. These sets were created and reviewed by the teachers on the DPLA's Education Advisory Committee.