102 Days of Lying About Lauren

After being abandoned by her mother in a most unusual place, a defiant heroine sticks to her plan for staying hidden—even though getting caught could mean saving her life.
Twelve-year-old Mouse calls an amusement park home.
Nobody notices her, and that's the way she likes it. Mouse sweeps the streets and wears a uniform she "borrowed" and sleeps on the top floor of the Haunted House of Horrors. She knows which security guards to avoid, eats the bagel left out each morning for the Ghost of Summer (a popular theme park legend), and even has the taco guy convinced that her lunch is paid for. She has her special hiding methods down to a science. 
But one morning, a girl named Cat comes looking for Lauren Suszek. Cat notices her, and Mouse doesn't like it. Mouse cannot let this nosy pest find out who she really is! If Mouse gets discovered living in the park, Mama might come back for her, and Mouse doesn't want that. Or—even worse?—Mama might not come back at all. 
Mouse knows she can lose this girl without blowing her cover. She just has to follow her rules. A carefully constructed life in the park is all she needs. Right? 
Anchored by memorable characters and an extraordinary setting, Maura Jortner's brilliant debut novel is bursting with grit, humor, and heart.
A Shelf Awareness Best Book of the Year!
A Junior Library Guild Gold Standard Selection