When Sam brings his baby brother to school for Show and Tell, he highlights the baby's pertinent traits for his classmates: He has a green carriage, he eats mushy baby food... and sometimes his diapers are really yucky. The sharing session leads to a discussion about how everyone was once a baby, and the children bring their own baby photos to school. Mr. Judd, the teacher, posts the photos, and at first all the babies look alike. A lot of them had no teeth to smile with, and some of them had no hair. But closer inspection singles out Jack, because of his curly hair, and another baby has Sacha's unique smile. Mara is recognized by her orange hair, and Anika by her large, dark eyes. Mr. Judd provides pertinent clues to help the class identify a few of the harder photos, but one picture stumps everyone. At last Mr. Judd gives a tip: This baby grew up to be very handsome. And very clever. But even though this baby is very grown up, he's still at school. The class catches on, and realizes that even their very adult teacher was once a baby. Amusing illustrations showing the baby Mr. Judd (easily identifiable because of his debonair black mustache!) in a highchair, drawing on walls, and in need of a diaper change, capture the amazement young children often feel when they realize their grown‑ups were once young, too. (Ages 3‑5)

After Sam's baby brother visits Mr. Judd's class, all the children bring their baby pictures to school and have a good time guessing which is whose. But there's still one picture left over. . . . It's Mr. Judd! Now the children can imagine their teacher as a baby (complete with mustache). The idea that everyone starts out as a baby--and that babies and kids become grownups--is conveyed with a light touch in this sprightly school story, which acknowledges young children's fascination with babies and with the idea that even the most revered grownups used to wear diapers. Readers will want to play "Guess the Baby" in their own classrooms.