Losing baby teeth is a rite of passage for all first graders, so the protagonist of this clever story should be excited about her loose tooth on the first day of school. She’s not. And it’s all because a second grader has told her that her new teacher, Mrs. Watson, is a 300-year old alien who needs human baby teeth in order to survive. Even though Harry Bliss’s hilarious illustrations show Mrs. Watson a quite an ordinary young woman, the second-grade informant has pointed to all sorts of evidence that support her theory: there’s her pearl necklace and earrings that look remarkably like teeth, and the mysterious “treat box” to avoid at all costs. And if you look closely, she says, you’ll see that Mrs. Watson has a green tongue. In spite of the first-grader’s best efforts to keep her mouth closed all day long, her tooth makes a dramatic exit in a toothsome story perfect for a first-grade read-aloud. (Ages 5–8)