Zibby Payne & the Trio Trouble

Everyone's favorite Total Tomboy, Zibby Payne, is back, with more of her precarious, and hilarious, navigation of the ups and downs of sixth grade.
Zibby's new best friend Gertrude and old best friend Sarah can't stand each other, so Zibby swings into action with Operation Friendship Campaign. And, it works ... too well! Gertrude and Sarah end up bonding more with each other than with Zibby, whose peacemaking efforts have resulted in Zibby Payne, Party of One.
As Zibby tries to figure out how to turn this smug duo into a happy trio, she discovers that Gertrude isn't who she seemed to be and in fact, purposefully drove Zibby and Sarah apart using not-so-nice tactics. Can Zibby save Sarah from the toxic friendship or will Sarah think it's just Zibby's jealousy talking?