Good question.
The book attempts to tackle the areas of class, race, gender, exceptionality, religion, language, and age; they want to illuminate the nature of these topics and explore the issues involved in approaching and including them in a multicultural classroom. Unfortunately, even though they divide the various demographics represented in our American pluralistic classrooms well, they rarely get into dealing with this problem very effectively.
The prolegomena they have (the first chapter) was supposed to explore what we mean by "culture". They co-opt Goodenough's definition, "a way of perceiving, believing, evaluating, and behaving," and that's, ironically, good enough as a starting point for trying to wrap your mind around these issues. Unfortunately, they immediately endorse a hyper-relativist perspective regarding the legitemacy of various ways of "perceiving, believing, evaluating, and behaving," which doesn't really set them up to grapple with this problem. Basically, they never provide a foundation of unity from which various groups can be included in a pluralistic classroom other than via their notion of democracy, defined through "cultural relativism", "social justice" and "equality". Though they try, there are no satisfactory explanations given to legitemate these ideas. They should have stuck to discussing how educators can effectively teach in classrooms where the students have a variety of worldviews/cultures than dabbling as amateurs in philosophy, anthropology, and politics. This book is, practically speaking, worthless.
Because their epistemological, anthropological and political assumptions color _everything_ that they say for the rest of the book, if you're not familiar with these areas, you'll never be able to meaningfully engage with this book, whether you agree or disagree. These assumptions of the authors guide the portraits they paint and evaluations they make of culture and the present pluralism, as well as informing their advice on how we ought to navigate a pluralist classroom as educators.
I suggest reading a bit in philosophy before trying to tackle this problem. Routledge has a great series to familiarize yourself with philosophical problems, I especially suggest their book on _Ethics_ by Harry Gensler. It is simply written, and very practical. That is a _perfect_ place to start figuring out how to deal with these practical (and partly theoretical) problems without introducing a "solution" that only brings more bad weather in the future.
