Book 1 of the S204 course is all about diversity. It covers quite a lot of taxonomy, the science of categorising living things. Now if there is one thing that taxonomists agree on, its that almost every part of the taxonomic tree is subject to disagreement.
The next part is about protoctists, what probably use to be called protozoa. Its those organisms that aren't bacteria, plants, animals or fungi. So its a bit of a mixture.
Finally the last part of the book looks at common laboratory organisms, such as rats, C. Elegans, zebra fish etc.
Its not the most exciting of books for me, though it is luckily fairly short at 138 pages or so.