Why does Woodson structure her memoir into five distinct parts

Jacqueline Woodson divides her novel “Brown Girl Dreaming” into five major, linear parts, running from Part I to Part V. Each part is further subdivided into chapters. Each chapter takes the form of a poem or lyrical free verse. Each chapter deals with a specific memory or incident, while each part focuses around a general time in Jackie’s childhood. For example, the chapter “New York City” describes Jackie’s first encounters and experiences with living in New York, while Part III, in which the chapter takes places, deals with life between New York during the school year and South Carolina during the summer.