I can't brag on this book series enough. This is not a book that is one thing, or even easily read in one sitting (though I have done it, on nights when he doesn't fall asleep quickly). This is the sort of thing that seems so basic to an adult mind, but my son grabs a new bit of information with each read, to the extent that he starts practicing talking about it, sometimes for days, and we pick it back up and the next read somehow he is even more interested in the parts we already read, as if to show he is anxious to reaffirm his new knowledge and maybe he is even checking if he recalled the details correctly. I am astounded at how this seemingly so simple book could provide such an endless stream of new information and ideas to help my son sort out his overactive 4yo mind. This is the fifth one of these I have bought, and sometimes I wonder if I should clear out his shelf and only have these, Golden Books, Seuss, and his favorite character Batman. He would miss all the books about Christmas, but I would not. This book in particular is working great to outline some important ideas I want my son to grasp before he gets his first pet. There is a nice sized section for the most common pets. I think the book about places and the one about people maybe interest my son just a little less, but not enough to make us avoid them. He does love King Tut now, so that is something. These are endlessly valuable and I hope they continue to serve him leading to preschool. I look forward to getting several more of these as his little kid books incrementally age off his shelf.