For many things in life there must be balance, and it's no different for money, and the promise to pay back a mortgage or other type of loan. The balance of money and promises in the US has gone awry, causing our financial crisis, which of course has affected the entire world. So, what happened? For a quick understanding of what happened to our economy, this is a great visual aid, and done in a simple enough manner that even your teenagers will understand.
Although it's not a complete picture of what occurred, it provides an understanding of the major challenges leading to our current economic woes. One point not mentioned in this video is the fact that our economy was also affected by corporate corruption, causing much distrust for investing in company stocks, which also had a major impact on our stock market. There are of course other reasons for our economic woes, but again this is a great visual aid and explanation for a basic understanding.