"Huge" means coffee table size, and roughly 500 pages. That's almost six pounds of enjoyable reading - if you decide to read it, rather than just letting the magnificent imagery wash over you. That's how the book starts, by the way. Page after page of full-page, full-color photos, including some two-page spreads, before you even get to the introduction.
It gets off to a slightly slow start, with a quick review of just what seawater is, chemically, and why that matters. Geology and meterology come next, the rocky basin that holds the sea and the air above it. In both cases, land and sky, the ocean shapes them as much as they shape the ocean. This discussion includes things as important as El Niño and hurricane Katrina. Although wide-ranging and informative, vivid illustrations and photos keep it lively and personal. The first 200 pages or so continue the discussion of the polar icecaps, shores, underwater geography, and the rest of the ocean itself.
Then the discussion turns to oceanic life. Historical life start it off, from the age of dinosaurs. The authors then move into the plankton, clearly distinguishing the bacteria from archaea, and both from the eukaryotic protists and diatoms. Next comes plant life in and near the ocean, including aquatic algae and shoreline plants, lichens, and fungi. These sections set the pattern, clearly identifying several levels of taxa to which specimen belongs, its worldwide distribution, gorgeous pictures, and a paragraph or two. Discussion varies, sometimes highlighting distinctive parts of an organism's life cyle, special relationships, or the scientists who've done most to uncover and spread this wonderful knowledge.
It's the section on animals that young readers will be most drawn to. It starts with the sedentary corals, bryozoans, and other beautiful and colorful critters of simple habits. The authors work their way up to bottom-dwelling benthos and the free-swimming nekton. That includes fish, sharks, porpoises and whales, turtles, and other wonderful beings. Next come birds, lizards, seals, and other lives spent on or only partly in the sea.
But you won't take it in order - you won't be let to if you have a kid in your lap when you read it. So much of this book is so exciting, even parts you might not have guessed, that you're sure to skip around, finding new surprises nearly every time you flip to a new page. It's huge fun, good science, and a great way to stir any child's (or adult's) fascination with the majority of the world's surface and the lives in it.