The New Girl By Nancy Krulik

(How I Survived Middle School #4)
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Bestselling author Nancy Krulik delves into the mind of a twelve-year-old who is trying to survive middle school.
Joyce Kilmer Middle School is holding a fundraising carnival, and Jenny and her rival Addie make a bet that each girl will raise more money than the other. The loser will have to wear her pajamas to school! The competition gets even hotter with the arrival of a stylish new girl. Will she join Addie's group, The Pops, or will she help Jenny and her friends? Someone's going to be wearing bunny slipper to school-will it be Jenny?