I used this book for a university course on child psychology and found it to be well-written, easy to understand and very informative. New terms are explained in the margins and there is a glossary at the end of the book. I still refer to it now and again as it is a really good resource. The chapter on the Russian teacher and psychologist Vygotsky, for example, is a good introduction to his vitally important work that is often ignored. Another advantage of Schaffer's work is that he uses examples from different cultures to illustrate and to test various theories.
If you have no previous knowledge of psychology then a chapter on child psychology/development in an introductory psychology text might be more suitable. But if you are familiar with basic psychological terminology this book should be fine.
I bought this as pre study for my upcoming course with the open uni, I am nearly half way through and finding the reading really useful, educational and feel this will defiantly help me. would recommend to all in childcare.