Many English words are based on Latin and Greek roots. These ancient root words are dependable and unchanging and serve as the key to understanding not only the vocabulary of English but many of the modern European languages as well. An understanding of the core meaning can provide a tool for unlocking the meaning of the thousands of Latin and Greek-based words. Eminently readable, this book will sustain the interest of both browsers and serious students.
Although this isn't really a kids book, I'm using this to help my kids understand language better. A few puzzling omissions, but still more often useful than not. You take an English word (e.g., "civic"), look it up in the back to find the Latin/Greek root ("civis"), then turn to the entry for "civis" to learn what other words are related to it. Fun for all the family.
I got this book to learn origins for vocabulary, but I didn't read too much of it before I got another vocab book and another, before not reading any of them much at that time. It is pretty cool though.