Kate Smith Milway's book, The Good Garden, does a good job of showing what life is like for subsistence farmers and the slow process of bringing change to places like the hillside villages in Honduras. The inclusion of websites to explore and facts to supplement the story are very helpful for classroom use. I've read her book One Hen, which is set in Ghana, with some of the classes at Fairview. We found the differences between our lifestyle and what was portrayed in the book very intriguing.
The story is told without being maudlin or condescending, which some authors seem to have a hard time with when they portray other cultures. I felt that having Maria Luiz help the new teacher with his garden and then try some of his methods out of curiosity was a good way to explain the value of the methods without being "preachy". It also shows that everyone in the family can contribute, even the children.
Our school works closely with Mountain Laurel Gardening Club and we have several raised planting areas around the school for class gardens. I can imagine using the book along with other resources as part of a gardening unit, with our students working in the garden as part of the lessons. We could try out some of the farming techniques shown in the book and see how successful they are in Tennessee.
The author's profile is on the Good Garden website. If you click on the "educators" link, you can watch a video of the real Maria Luiz that the girl in the book is based on.