It really is strictly for the very youngest students (PreK-K), as a tool for allaying fears or nerves that may arise from having a substitute teacher.  The illustrations are cute and inviting and support the text.  The story is written in rhyme, but I’m afraid the rhythm is a bit stilted/awkward at times.  It tells of a small kitten’s worries when she doesn’t see her teacher there to greet her as usual, and the questions that she has about how they will manage without her, but of course in the end it all turns out just fine.