Every year, the Parent-Teacher Organization of Hiller Elementary School gives every teacher a fifty dollar bill to help offset classroom expenses. This year the author, a second grade teacher, knew exactly how he would spend the money. He bought thirty-eight perfect, clear, two-quart plastic, lidded containers for each of his students and three small ceramic aquarium castles. This article describes how the students created homes for guppies. (Contains 1 online resource.)