In the city of Boston, / in fair Franklin Park, / sits a snug little zoo / that closes at dark. One morning the keeper / discovered a note. / We''ve gone for a walk / the animals wrote. ''Oh, dear, said the keeper, /what am I to do? / My critters have left me / alone at the zoo. Children will have a ball helping the keeper find a rhinoceros in the North End, a koala bear in Chinatown, and a penguin on Boston Common. Over 100 animals are hiding cleverly in beloved Beantown settings.