Animorphs Book 49: The Diversion by K. A. Applegate

The Yeerks suspect the Animorphs are human, Tobias has another chance at family. This book changes a lot of the previous status quo, continuing the shift from hiding and secrets to full out battle with the Yeerks.

I like this one, it's a good mix of cautious and sweet, and I'm really happy for Tobias. The updates on the status of the Hork-Bajir colony with regards to Rachel's mom are pretty great. It's also very frantic and scary, especially at the very beginning and very end of the book.