Margaret Simon is an eleven year old at summer camp, when her parents decide to move from exciting Manhattan to sleepy Farbrook, New Jersey. Margaret is dealing with the crucial transition from eleven to twelve, but she's got a whole new culture to figure out too. People are super concerned with what religion she is, but Margaret doesn't have a religion. Her mom is Christian and her dad is Jewish who were meant to be together. Good thing she's got her friends. Nancy Wheeler, Gretchen Potter, and Janie Loomis form a knitting group to talk about boys, school, puberty, and all the other stuff.
But Margaret doesn't just have her best buds, she also has God. She may not have a formal religion, but that doesn't bother her to have her regular chats with "The Big Guy". So Margaret makes her way through sixth grade the best she can. She tries out a bunch of different religions to see if one fits. She meets her long-lost grandparents, she spends a lot of time worrying about when she'll get her period, she gets a crush on an older boy, and she goes to her first supper party. Through it all, she comes back to her best friend God.