Disney Adventures Magazine was a monthly magazine targeted toward grade-school kids, published from 1990 to 2007. It contained articles and ads about Disney productions and areas of general entertainment interest. During the time the Animorphs series was published, Disney Adventures featured several articles and ads, mostly about the TV show and the games, not the books.
This mini book (which contained Chapter 16 of Book 1 The Invasion) came with an Australian issue of Disney Adventures Magazine circa summer 1998 when book 19 was published. A similar preview booklet was included in an issue of Nickelodeon Magazine, but it was larger and contained three chapters (16-18) instead of just one.
Front and Back cover
Inside front cover stating "Titles 1-19 Available Now" and the first page with the Animorphs series summary.
First page of Chapter 16
Last pages of Chapter 16 and the Jake/Lizard side view morph
Last inside page advertising animorphs.com.au
Comparison of the covers of the preview booklets found in Nickelodeon Magazine and Disney Adventures Magazine.