Reviewing recent research on efforts to improve the quality of public schooling in the United States, this paper focuses on evidence suggesting that negative by-products often accompany innovations and, moreover, that innovators have tended to disregard their capacity for leaving schools in worse condition than they found them. The analysis concentrates primarily on efforts to make an impact through external funding--the project approach to innovation. Several of the illustrations are drawn from the experiences of the Teacher Corps and its numerous projects, including one that involved the author. The change process is divided into three stages: (1) the planning stage, during which proposals for projects are conceived, developed, and funded; (2) the implementation stage, when the proposed impact is expected to be made; and (3) the evaluation stage, when the degree to which an impact has been made is assessed. The three stages overlap at certain points and are not regarded as mutually exclusive or temporally discrete. Recommendations for avoiding negative by-products are made, and consideration is given to the value of incremental change. (Author/MLF)