In Western agriculture, unless a wheat- or cornfield is left fallow every few years, the soil becomes exhausted. Every winter, fields are empty. The hard labor of spring planting and fall harvesting is followed, like clockwork, by the slower pace of summer and winter. This is the logic the reformers applied to the cultivation of young minds. We formulate new ideas by analogy, working from what we know toward what we don't know, and what the reformers knew were the rhythms of the agricultural seasons. A mind must cultivated. But not too much, lest it be exhausted. And what was the remedy for the dangers of exhaustion? The long summer vacation—a peculiar and distinctive American legacy that has had profound consequences for the learning patterns of the students of the present day.