Something of great importance entrusted to fourth-grader Effi Maloney has disappeared and shes sure her big sister, Maxey, had something to do with it. Effis no pushover, but trying to stand up to Maxey is like trying to stop an earthquake. It would be easier to deal with Maxey if Effi had a buddy. She hasnt had a best friend since Lola Jo moved, and she has so many secrets saved to tell a best friendincluding the most amazing idea in the world for a winning science projectshes about to explode.Effis got to win that science prize, find a best friend, and get back at Maxeyin just one week!From the Hardcover edition.