What is the author's style in My Darling, My Hamburger by Paul Zindel?

The story is told from the third person omniscient point of view. This gives us a look in to the mind of any character the author chooses. For such a short book, the author has several structural elements at work. In addition to the basic narrative, the author incorporates handwritten notes between Maggie and Liz, a note from Mr. Zamborsky's office to Sean, a letter Liz writes to Sean on the paper place mats of a restaurant, excerpts from astrological magazines, a notice of a school dance, the text of Sean's essay and the text from the graduation announcement for the senior class.