Pippi Longstocking by Astrid Lindgren
Pippi Longstocking is a children's book written in 1945 by Astrid Lindgren. Pippi is a 9-year old that lives in an old villa in a Swedish town. (which remains unnamed for the series) She meet Tommy and Annika, 2 children living next door. They then have all sorts of adventures, including searching for odds and ends, (including lumps of gold) having a picnic in the woods, and introducing Pippi to school (see article on Pippi Longstocking)