Jennifer Thom’s first single-authored book is an engaging and organic approach to complex learning theory and mathematics. At first glance, the reader is met with an intertextual exploration of mathematics education through ecological sensibility, thought, and diverse ways of knowing. Yet what is most striking about this book is its playfulness, and the ease with which Thom explains concepts. As the reader opens the first page, she/he is invited to consider the living systems of a tree as an analogy of learning systems, and is invited to interact with this book as one might with various parts of a tree: “that any one leaf is neither directly connected to the other leaves nor does one need to view them in any particular sequence” (p. xi). Through this acknowledgement of parts, Thom also accepts the interconnected nature of mathematics and an ecological sensibility. What follows this initial statement is a key, of sorts, to help interpret the intentional complexity of the text, visuals, font choice, shading, and type-setting.