Deedee is a book-only student in Mrs. Jewls' class. She is described as being mousey looking. She made a plan with Todd to get thrown out the window to get to recess and get a red or green ball. Mrs. Jewls found out about the plan and sent Todd home on the Kindergarden Bus but she did not send Deedee on the bus.
She is a girl who is fairly interested in sports, though often, this can be troubling for her, since often she is stuck with the yellow ball, which can't bounce, and goes in the wrong direction whenever it is kicked. She seems to be good at problem-solving, since she realized who Mrs. Drazil was before any of the other students.
The first book describes Deedee as "mousey-looking", which helps her diguise herself as a dead rat to get a green ball in her chapter. She also wears a flowered T-shirt as described in the third book.Her voice is described as sounding "small, but full of energy".
In Sideways Stories from Wayside School, a chapter called "Deedee". In this chapter, she tries to get a green ball, eventually leading to her disguising herself as a dead rat so she can get to the playground first.