Ever tried teaching with technology? No, we don't mean Twitter, Facebook, iPods, cutting-edge interactive whiteboards, or even video and DVD players.

We mean patents.

The U.S. Patents and Trademark Office and Google Patents stockpile millions of patents, dating from 1790 to the present. In a July 2010 Organization for American Historians article, Chemical Heritage Foundation fellow Cai Guise-Richardson suggests ways to mine these historical document collections for classroom use.

Maybe you're studying Eli Whitney's cotton gin. What did the original patent look like? Can students decipher what the device does and how it works from the diagrams alone, or is it unclear? What sort of language does Whitney use to describe his invention, and how does he think it will help society?

Ask your students to think about the technology they encounter every day. Do laptops, MP3 players, cars, phones, household appliances—even toys—ever stop changing? No—there's always a new model or a different brand to buy. Inventions in the past developed in the same way. Try a Google Patent search for "cotton gin" to discover just how many variations and improvements on Whitney's invention eager inventors have developed since 1794, when Whitney first patented his design.

Try an advanced search using a word and a date. In 1901, were there any patents containing the word "genetics?" Probably not. What about in 1954, the year after scientists Watson, Crick, and Franklin discovered the structure of DNA? How about in 1990?

Think of other terms that might show up frequently in patents in different time periods. Is "bomb shelter" more frequent after World War II? How were radioactive substances used before they were proved dangerous? Consider this 1925 patent suggesting that rendering food and water radioactive will help prevent disease and preserve freshness. Do students think we're using any inventions today that we'll wish we hadn't in the future? What sorts of words and phrases do they think would show up frequently in patents today?

Pick a phrase or an invention and start exploring! Refer to Guise-Richardson's article for more suggestions if you have difficulty searching or run dry of ideas.

Teaching materials in both Spanish and English can be difficult to find, and a new bilingual exhibit—inhouse, online, and scheduled to travel—from the Smithsonian Museum of American History explores a little known chapter in the history of Mexican labor. Bittersweet Harvest: The Bracero Program 1942-1964 looks at the largest guest worker program in American history, when an estimated two million Mexican men came to the United States on short-term labor contracts.

The exhibit, according to the Smithsonian, tells a story of both exploitation and opportunity to earn money. Small farmers, large growers, and farm associations in California, Arizona, New Mexico, Texas, Arkansas, and 23 other states hired Mexican braceros to provide manpower during peak harvest and cultivation times.

"This exhibition allows us to explore complex issues of race, class, community and national origin while highlighting the irrefutable contributions by Mexican Americans to American society," said Brent D. Glass, director of the museum.

The presentation is divided into multiple themes including Expectations, Family and Community, and Life in the United States. The Bracero History Archive supplements and complements the online exhibit. Almost 3,000 images, documents, and oral histories comprise the Bracero History Archive, and the public is invited to upload further contributions. Historian Steve Felasquez talks about how he gathered oral histories for the project and of their significance.

On the Archive site, Lesson Plans designed for students grades 6-12 engage students with photos, oral histories, and documents.

A 1939 library sit-in in Alexandria, VA, is often called "the most famous civil rights protest you never heard of." And recently, third-graders from Samuel W. Tucker Elementary in Alexandria explored this episode in the history of civil rights in their own backyard.

They shared their findings to a standing-room-only audience at the Barrett Branch Library where the sit-in took place.

The Alexandria Library stands as a testament to one of the first challenges to Plessy vs. Ferguson. It began when George Wilson, a retired Army Sergeant, was persuaded by 26-year old Samuel Wilbert Tucker to challenge the status quo and apply for a library card at the Alexandria Library. The sit-in didn't desegregate Alexandria libraries, but it did lead to construction of a library branch for African Americans completed in 1940.

The Alexandria, VA, Black History Museum bills this action as The Nation's First Sit-In in the lesson plan America's First Sit-Down Strike: The 1939 Alexandria Library Sit-In that emphasizes teaching with historic sites, exploration of primary source documents, and critical thinking. The introduction to the lesson plans places the sit-in in historic context, highlighting the educational climate for African Americans at the time. As Tucker recalled, "I finished the eighth grade in Alexandria and the state of Virginia said that was to be all the education I got." (Tucker was an attorney at the time of the sit-in; he had attended Howard University, graduated in 1933, and passed the Virginia Bar exam that same year.)

The eight-year-olds who recreated their research at the Library met the relatives of five African American men jailed the day of the protest as well as Frederick Day, the 91-year-old former chair of Alexandria's Board of Education who was also the first African American public school board chair in Virginia.

Day recalled, "A lot of people come to my hometown and think that it was like this years ago, but they are far wrong. It was a typical Southern port town, with all the problems of the deep South."