In 1940, 12-year-old Cuban boy Fidel Castro wrote to US President Franklin Roosevelt to request a $10 note.
'If you like give me a ten dollars bill green american in the letter'
The hand-written letter, embellished with an elaborate signature, has been unearthed by the US National Archives and Records Administration.
It was one of the thousands of letters sent to the White House by children taking their demands to the very top.
In an impeccable hand, young Fidel signs the letter to President Roosevelt : "Your friend".
Dear Mr President
He asks Roosevelt, President of the US between 1933 and 1945, to fulfil one desire - to send him a green $10 note.
"Never I have not seen a ten dollars bill green American and I would like to have one of them," the future Cuban leader wrote.
He included a return address at the Colegio de Dolores in Santiago, Cuba, where he was studying at the time.
The White House had an office to deal with all the president's correspondence and sure enough Fidel Castro received a reply, but disappointingly, no bill.
About 19 years later, his guerrilla campaign toppled the seven-year military rule of Cuban President Fulgeneio Batista and, at 32, Mr Castro became the country's new leader.
The letter was lost for two or three decades and only found by accident by a researcher.
Other letters to go on display at the National Archives and Records Administration include that of a boy called Andy Smith who wrote to Ronald Reagan in 1984 to ask for federal funds to help him clean up his room.
Another is from three girls begging President Eisenhower to spare singer Elvis Presley from conscription and, more importantly, to save his sideburns.
"My girlfriend's [sic] and I are writting [sic] all the way from Montana. We think its [sic] bad enough to send Elvis Presley in the Army, but if you cut his sideburns off we will just die!" they wrote.
Nowadays children can still put pen to paper and write to the US president at his Pennsylvania Avenue address but they are more likely to send an e-mail to email@example.com.