A school project on the Holocaust (the murder of six million Jewish people, and millions of other people, in Europe from 1933 to 1945) attracted so much attention around the world that a film has been made about it called Paper Clips.
The eighth grade pupils at Whitwell Middle School in America didn't understand what six million looked like - so their teacher came up with the idea to collect that amount in paper clips, to help explain it better.
The pupils sent letters out to people asking for paper clips - but it was going to take 10 years to collect the number they wanted at the rate they were going. That was until media coverage from TV and newspapers made the project take off.
Paper clips came pouring in by the millions. In six weeks they had received 24million - and everyone in the small town, from grannies to aunties, had to count them! There was so much post, the school kids had to collect it themselves.
Letters from people who had lost relatives in the Holocaust taught the children that not everyone is lucky enough to grow up with grandparents, aunts, uncles and cousins.
Some people who had survived the Holocaust visited the school as they were so inspired by what the pupils were doing. They talked about what had happened to them and spoke of their hope that it would never happen again.
After three years the project had collected four times the original number planned and the school was flooded with them. It was decided to put the paper clips in a permanent memorial.
A cattle truck was found which had been used in Germany to transport Jewish victims to the concentration camps. It was shipped over to the school in 2001.
Eleven million paper clips went into it in total - six for the Jewish people killed and five for the other people Hitler and the Nazis murdered because they were considered 'different'.
Since then the memorial has regular visitors who learn what intolerance can lead to if you let it, and how you should treat everyone as you want to be treated yourself. And the film of the project has now been released too.