Here are some Freedom Card responses:

CNN’s Christiane Amanpour: “Freedom means the freedom to speak, to worship, to VOTE! and the freedom to take politics SERIOUSLY!”

Film maker Ken Burns: “True freedom is the complicated negotiation between what I want and what we all want and need.”

Former President Jimmy Carter: “Freedom is the essence of democracy and human dignity.”

Film maker Wes Craven: “Freedom to me is room to create scary movies.”

Pro Football Hall of Fame coach Tony Dungy: “Freedom means the opportunity to utilize our God-given talents to honor Him in a way that helps other people.”

Talk show host Larry King: “Freedom is the Bill of Rights, especially the First Amendment.”

Singer/songwriter Cyndi Lauper: “The right to act, speak or think without hindrance or restraint.”

Alex Robson is likely one of the few people on the planet who has exchanged letters with former President Bill Clinton and the infamous criminal Charles Manson.

How’d he do it? He asked them to talk about freedom.

For nearly a decade, Robson, a Gwinnett County teacher, has asked politicians, entertainers, athletes, families whose loved ones were killed on foreign battlefields, students and prisoners to explain to explain what freedom means to them on 3 x 5 index cards. Robson started the project in 2007 as a student at Gwinnett’s Mill Creek High and estimates he’s collected about 4,000 Freedom Cards.

» GALLERY: See a few of the cards Robson has collected

Freedom is being able to be who you are without being mocked for your race, religion or sexuality — Elton John

Robson started the project because he was frustrated by the political acrimony in America and wanted leaders to think about what unifies them. Today, he said the political divide is more contentious, but Robson continues to collect thoughts from the famous and not so famous.

“I feel like it does a good job of getting a slice of what America is all about,” said Robson, who teaches at GIVE Center West, an alternative school.

Among those with Georgia connections he’s collected Freedom Cards from are former President Jimmy Carter, musical legend Elton John, CNN founder Ted Turner and Atlanta Falcons head coach Dan Quinn. Other well known people who’ve sent cards include U.S. House Speaker Paul Ryan, former U.S. Supreme Court Justice Sandra Day O’Connor, South African Archbishop Desmond Tutu, talk show host Larry King and entertainer Carol Burnett.

Robson’s proudest of the card he received from former U.S. Secretary of State Henry Kissinger.

“He’s seen so much history,” Robson said.

The responses are sometimes written in letters. Some are more succinct.

“Freedom: elbow room,” wrote famed attorney F. Lee Bailey on the back of one of his business cards.

Robson said the responses help teach about social studies. He’s also noticed reading the cards helps students improve their writing skills.

More recently, Robson has reached out to death row inmates, prisoners in some of the nation’s highest security prisons and Syrian refugees to get their thoughts about freedom. The responses, he said, have similar themes, such as not imposing your viewpoints on others.

Robson, occasionally with the help of his parents, sends letters to prospective freedom card writers and return envelopes. He also contacts people he’d like to hear from via social media and through his website. He also visits locations where he thinks he’ll get some interesting responses. Last summer, Robson attended Black Lives Matters protests in Atlanta and went to the Republican National Convention in Cleveland. He plans to attend the presidential inauguration in January.

Freedom gives me the ability to dream big and know nothing is impossible if your goal is an honorable one — Carol Burnett

Most people respond to his request. A few have not, such as Gov. Nathan Deal and Atlanta Mayor Kasim Reed. Hint, hint.

Robson has tried frequently to get a card from President Obama, visiting sites when he’s been in Atlanta.

“It will happen one day,” Robson said of Obama.

Others on his wish list include Wikileaks founder Julian Assange, writer Gay Talese, former Soviet Union leader Mikhail Gorbachev and rap star Kanye West.

Freedom is the very oxygen of the human spirit — Joyce Carol Oates

Robson said he tried Manson for about nine years before the convicted killer sent a card in September. Manson’s card and letter were, Robson said, “disturbing” and “crazy.” It was much different than Manson “family” member Susan Atkins, who’s response he described as far more thoughtful.

“Freedom is choice in thoughts, words and deeds,” wrote Atkins, who has since died. “And the responsibility to live with the consequences of those choices, which can include and encompass the entire spectrum of human emotions and experiences. Freedom is far more than liberty of physical movement. Every decision each human begin makes, first with the freedom of choice, is to act or not to act, based upon the information which calls upon the person to make a decision.”

Someday, Robson said, he may publish a series of books from the cards.

And what does freedom mean to him? Robson said he’s still working on his own definition.

Robson said his goal is to collect enough cards for future generations to understand what America was like at this point in time.

“When I feel like we’ve captured that fully,” he said. “I will know the project is done.”