This is a lovely little book that I bought as a present for my (7 year old) daughter. She enjoyed it as a picture book, but hasn't really engaged with the plight of the different creatures and habitats (yet?). However, we have used it to plan days out, by going to some of the places mentioned in the book.
Note that this is not a huge coffee table book.
This book does make you think, and the team that put it together have made some interesting choices of what to include in their 100.
Buy the book and support at least one of the organisations mentioned in it - pick an unconventional subject and you never now what you might learn.