Metal Detecting

by Emily

I understand that metal detecting is becoming more and more popular these days and I'd like to find out more about it.

I found this picture of a Sunday School picnic on the web. I think it's American and it's obviously old. They are searching for pennies but seem to have no detection equipment as such.

Can anyone tell me what this is all about? Does anyone have any metal detecting stories or information about picnics combined with searching for coins and other valuables?