Race, Ethnicity, Gender, & Class

Race, Ethnicity, Gender, and Class: The Sociology of Group Conflict and Change
by Joseph F Healey
I just started my new classes one of which is on diversity; this is the textbook from the class. I hate to say it, but I'm already disappointed. The short discussion on gender had articles from "scientists" who believe that gender roles are biological and completely omit evidence of pre-Christian societies where women held positions of power that in Christian society were deemed only appropriate for men. They also hardly even mention the GLBT community as a minority, which seems ridiculous with how much this issue is in the forefront of politics and business. The short mention only includes gays and lesbians with out a mention of bisexuals or transgender persons at all. I've read the first chapter and if this is a good representation of the rest of the book it was a huge waste of money.
**Update**
Well I am realizing this book is good for what it is, not what the class description claimed it would be. This book is mainly about race & ethnic relations as minorities and that's it. The class claimed to be about minorities in regards to race/ethnicity, gender, sexual orientation, age, disability and class. So my wrath should be directed at the school for it's misleading class description. I still stand on my reasons above they are just now directed at the curriculum instead of this book in particular. Following is the course description from my degree handbook.

"ETH/123 Cultural Diversity: This course is designed to educate students about issues of diversity, including, but not limited to, race/ethnicity, gender, sexual orientation, age, disability, and class, and to provide the tools necessary to promote a more respectful and inclusive society."