If children grew up in a world devoid of cultural context, the picture painted of children by developmental psychology textbooks might be quite accurate and therefore adequate. The problem is that not even children confined to so-called bubble worlds because of severely impaired immune systems grow up in such a world. The result is that students of developmental psychology, and even of psychology in general, acquire knowledge structures about development that are incomplete and, in many respects, wrongheaded. We, as developmental psychologists, thereby do our students an injustice.