We bought this book at the Homeschool Conference in 2010 and I finally read it this past month. When we bought it we had two sons (now we have three!) and we want to help them develop a heart to provide for their homes. Being able to live as a single-income family means one parent can be at home and homeschool if this is how God leads.
The book cautions against allowing appetites to develop which will essentially be a waste of time and not provide value to the family. One of the things they mention is team sports. Sometimes cited as a way for children to learn to work hard with others, Maxwell explains that children can develop teamwork by working with siblings, and develop the ability to work hard by helping with home repair. The cost of team sports may be that the family is at the mercy of the coach's schedule. The children will be associating with others without your influence, and you may have to sacrifice important evening routines.
One of the things I like about this book is that they have chapters for ages three to six, seven to twelve, and thirteen to graduation, as well as post high school. I can easily refer to the chapters that most apply to me right now to get ideas of things I can do with my children to help them develop the heart and skills that will make them successful.
I would recommend this book to any parent as I believe the admonitions around the development of appetites apply to all of us.