It's So Amazing: A book About Eggs, Sperm, Births, Babies, and Families

Harris, R. (1999). It's So Amazing: A Book About Eggs, Sperm, Births, Babies, and Families. Somerville, MA: Candlewick Press.

This is an encyclopedia on everything a parent would need to teach their child concerning sex. It includes diagrams and functions on all body parts. It talks about how puberty will effect your body. It goes into the scientific explanation of how babies are made: a sperm meets with an egg. It also talks about the physical act of making a baby: sex. Then the book shares different ways babies are born. The sex education continues in discussing different STDs. 

The author's purpose is to inform readers on all aspects of sex and our bodies.  I wouldn't include it in a school as not every parent is ready for their child to learn about every aspect of sex. I respect the fact that families can choose when to introduce various topics to their children. I would include it my home. It is a very good detailed resource and I think it could answer almost any question my children could ask.