The Digital Public Library of America (DPLA) serves as a portal to the digital collections of more then 40 state, regional, and online-only libraries, museums, archives, and other cultural institutions. Created to strengthen access to public resources and to "create novel environments for learning, tools for discovery, and engaging apps," the DPLA is an invaluable first stop for teachers and students looking for primary sources, particularly regional history sources.

Visitors to the website can search the more than 4,500,000 objects in the collections of participating institutions using keywords, returning results they can filter by format, owning institution, partner, date, language, location, and subject. Clicking on an object brings up detailed metadata, including creator, date of creation, and a description of the object, as well as a link to its original location online. Visitors who create a free account can save their search results, make them private or public, and share them via Facebook, Twitter, or Google+.

Visitors can also browse objects on a map or timeline—a fantastic way to prompt thinking about how primary sources are located in time and space. The timeline stretches from 1000 BCE to the present. (Note that zooming into the map returns finer results.) In addition, more than eight virtual exhibits demonstrate how DPLA sources can be curated to tell stories about themes and events.

The DPLA's API (application programming interface) allows visitors with the know-how to create apps drawing on the DPLA's collections. An eclectic set of more than 10 apps lets visitors browse DPLA's search results as a "river of images," discover primary sources related to their Zotero bibliographies, and more.

A fantastic starting point for anyone looking for primary sources, teachers can feel confident pointing students towards the DPLA to begin research projects or turning to the DPLA themselves to find resources to support lesson plans.

The private organization behind this website is in the process of digitizing millions of records from the Lincoln Administration (March 4, 1861, through April 15, 1865), drawing from collections at the National Archives; the State Treasury, Justice, and War Departments; and other federal offices and agencies.

These records include pardon case files, applications for Federal jobs, the papers of Generals Ambrose Burnside and Henry Halleck, records on the capture of Jefferson Davis and the John Surratt trial, and numerous telegrams and letters about all aspects of Presidential business, as well as maps, photographs, and newspaper articles.

Though the majority of these records are accessible by subscription only ($150/year for individuals, more for school districts and libraries), a few are freely available at the website: thumbnails of 35 photographs (most available in higher quality elsewhere), and roughly 50 political cartoons (too small to read).

More useful for the non-subscriber is the inclusion of 100-200 word descriptions of many of the newspaper publications included in the archive, as well as video footage of several scholarly conferences and presentations about Lincoln.

An interactive timeline of Lincoln's entire life is also included, interspersed with video footage of scholars discussing important events, as well as staged audio recordings of several of Lincoln's letters and speeches, such as a letter he wrote to Mary Owens in 1837 before she broke off their courtship.

For teachers, the website presents a list of 20 links to outside lesson plans covering many themes in Lincoln's life and Presidency.

The stated purpose of this website is to provide an overview of World War I. This it does effectively through hundreds of essays, 3,100 encyclopedic entries, 618 biographies, 318 resources on the war's major diplomatic and military events, and a timeline. Primary documents include over 100 diaries and firsthand accounts of soldiers and politicians, 3,900 photographs, 651 propaganda posters, and 155 audio files of songs and speeches. Documents include treaties, reports, correspondence, memoirs, speeches, dispatches, and accounts of battles and sieges.

The site also provides 95 essays on literary figures who wrote about the war. While admittedly a work-in-progress, the site offers much material on the leaders who engaged their countries in war and on the experiences of ordinary soldiers who fought the battles.

Emma Goldman (1869–1940) was a major figure in the radical and feminist movements in the United States prior to her deportation in 1919. This collection of primary resources includes selections from four books by Goldman as well as 18 published essays and pamphlets, four speeches, 49 letters, and five newspaper accounts of Goldman's activities.

There are also nearly 40 photographs, illustrations, and facsimiles of documents. Additional items include two biographical exhibitions, selections from a published guide of documentary sources, and four sample documents from the book edition of her papers. A curriculum for students is designed to aid the study of freedom of expression, women's rights, anti-militarism, and social change. The site offers essays on the project's history and bibliographic references as well as links to other websites.

The more than 3,500 full-text documents available on this website address the legal, economic, political, diplomatic, and government history of the U.S. Documents are divided into five time periods—pre-18th, 18th, 19th, 20th, and 21st centuries—and include treaties, presidential papers and addresses, and colonial charters, as well as state and federal constitutional and legal documents.

The materials are categorized into 64 document collections as well, such as American Revolution, Federalist Papers, slavery, Native Americans, Confederate States of America, World War II, Cold War, Indochina, Soviet-American diplomacy, and September 11, 2001. By clicking "What's New," the latest digitized documents become available. Material also can be accessed through an alphabetical list of 350 more specific categories, keyword searching, and advanced searching. Most of these documents are directly related to American history, but the site includes some materials on European and modern diplomatic history.

Presents about 50 facsimile reproductions and transcriptions of original documents, newspapers, books, autobiographies, biographies, portraits, and maps from the 18th and early 19th centuries. Examples include the Declaration of Independence, the Jay Treaty, George Washington's journal of his trip to the Ohio Valley, published in the 1754 Maryland Gazette, and 15 contemporary obituaries of well-known figures. Portraits include 24 statesmen and 12 "notable women." The site also furnishes guidelines for deciphering early American documents; seven "short films of noteworthy events," including a 35-minute feature entitled "The Life of George Washington"; four discussion forums; a collection of interactive crossword puzzles; the online journal, The Early America Review; and a news-ticker relating events that occurred "On This Day in Early America." Includes an "Early American Digital Library" from which visitors can view more than 200 digital images from early American engravings of people, places, and events (full-size images are available for purchase). Created by a collector of early Americana.

Using images, maps, timelines, and essays this "web-based documentary" relates the story of John Horse and the Black Seminoles, a community of free blacks and fugitive slaves allied with the Seminoles of Florida in the 19th century. Taking the position that academic historians have overlooked and misinterpreted the history of the Black Seminoles, it presents their role in the outbreak of the Second Seminole War (1835-1842) as the "largest slave rebellion in U.S. history." "Overview" provides an introduction to the features of the site and its interpretive themes as well as a "story synopsis" with a summary of the origins of the Black Seminoles, their role as rebels against slavery, their movement to Indian Territory after 1838, and a biography of John Horse. "Trail narrative" explains the history of the Black Seminoles "from their origins as a community to the death of their great leader John Horse in 1882" through 450 story panels with text and images. There are 360 "images," a picture tour with 32 images summarizing the site author's interpretation, and 23 "key images."

Other features include a key events summary, a guide to six central characters, a timeline, four interactive maps, and a listing of 17 related journal articles and nine newspaper articles available on the web. In addition to those interested in its interpretations of the history of the Black Seminoles and the Seminole War, this site offers useful material for those interested in Native Americans or the history of slavery in America.

Introduces the Omohundro Institute, "the only organization in the United States exclusively dedicated to the advancement of study, research, and publications bearing on the history and culture of early America to approximately 1815." The site provides background information about the institute, including descriptions of its fellowships, publications, conferences, and colloquia.

Also provides tables of contents and texts of selected book reviews from recent editions of The William and Mary Quarterly, articles from Uncommon Sense, and four links to related resources—including one to the Institute's own online discussion forum, H-OIEAHC, which offers 13 syllabi for undergraduate courses on early American history, a bibliography of approximately 50 titles, and links to 102 libraries, museums, historical societies, organizations, online exhibits, and collections of documents pertaining to the period. These latter materials can be valuable to students and teachers of the early American period.