Specifically, it is 8.5" x 10.6" with six fold-out pages which combine with the fold-out front and back covers to effectively make 28 pages of content. The front cover features a pair of red/blue 3D glasses. Stapled at the centre of the book is also four sheets of stickers.
The artwork is extracted from the various 8" x 8" books in the Marvel: Origin Story Books, specifically content is taken from The Amazing Spider-Man vs. Doctor Octopus (Origin Storybook), The Amazing Spider-Man vs. Mysterio (Origin Storybook) and The Amazing Spider-Man vs. The Lizard (Origin Storybook).
There's also some content featuring Kraven, Electro and the Rhino. I'm not sure if that's original content created for this book, or perhaps just taken from another "Origins" book that I haven't yet seen.
Some of the 80 or so stickers are designed to be placed at specific points within the "activity" book. Others are just generic stickers for putting on your wall, or your books, or whatever.
Like all the 3D books by Parragon and Scholastic, the 3D effect is a rather underwhelming. The text isn't much to write home about either: "Spider-Man's spider-sense is tingling! A crazy criminal is on the loose... it's Electro, and his powers are charged to the max!"
Still, the four pages of stickers is relatively generous, and the fold-out content and all-glossy pages give this book a bit more impact than most.
In fact, given the U.K. recommended retail price of £3.99, this is actually pretty good value, for which I have to give it credit.
So yeah, this book may be a confused mess of content. But at least it's a reasonably priced, confused mess of content.
Two and a half webs.