MAY, Eleanor . Lost in the Mouseum . ISBN 9781575656434 ; ISBN 9781575656441 ; ISBN 9781575656458 . LC 2014038449. ea vol: illus. by Deborah Melmon. 32p. (Mouse Math). charts. diags. Kane Pr. 2015. lib. ed. $22.60. pap. $7.95. ebk. $22.65. PreS-K The books in this educational series blend fictional stories with math concepts. In Albert Starts School , a young mouse learns about the days of the week and the importance of following rules when part of a group. In Lost in the Mouseum , Albert and his friend Leo are left in charge of Penny, the young sibling of a friend, at a museum. When Penny gets lost, Albert and Leo run through the museum until they find her right where they thought they lost her, in the process giving readers a primer in the difference between right and left. Both stories are simple and will appeal to their intended audience. Bright and cheery, illustrations are reminiscent of those of Rosemary Wells. Charts, diagrams, and bold red font make the math concepts clear. It's not always clear from the cover which theme each title explores: a minor flaw. Each title also includes extension activities for reflection, engagement, and further thinking. VERDICT A recommended purchase for collections looking for math concept stories. Jasmine L. Precopio, Fox Chapel Area School District, Pittsburgh, PA