Cool deal, Monty, let us know how you liked it!
It's quite good, despite being aimed at children. The author collaborated a lot with Clyde Roper on it, so there are actual architeuthis dissection photos as well as a number of pictures of living humboldts and sepioteuthis (which she's very good at pointing out as not architeuthis). It's very good about covering the science without dumbing it down so far that it's "not the whole story"-- there are some tiny nitpicks I have (like the description of the chromatophore musculature) but they're very slight.
It's also just a great source of a bunch of close-ups of architeuthis anatomy in various stages of dissection, with parts labled and whatnot... and it doesn't skimp on interesting facts about squid anatomy and physiology, although I expect most of what's covered people reading TONMO have picked up on their own, I certainly didn't know most if it when I was at the grade school age it's written for...
One question that I have, though, is that in describing the fact that architeuthis tentacle suckers can taste, she brings up the hypothetical scenario that a giant squid could stick its tentacles into cracks in the rock, grab onto something, and know if it wanted to eat it by tasting it with the suckers. This certainly sounds like the kind of thing an octopus would do, but I've never heard of any squid, giant or otherwise, reaching into cracks or nooks with its tentacles-- the tentacles in squids and cuttles seem very much optimized for open-water linear strikes rather than reaching into nooks and crannies and feeling around... in thinking about the lifestyles of most squids, I'd think architeuthis (and all squids I can think of except maybe bobtails) don't spend much time near reefs and rocks, in the sense of going after animals hiding in holes. Even cuttles seem like they mostly go after prey that's strayed from holes; I've never seen video of a cuttle pulling something out of a hole... Am I just unaware of decapods being observed reaching into nooks and crannies, or was this perhaps the author incorrectly extrapolating an octopus fact to squids?