Their research confirmed the prediction. This result seems to hold whether the unit of analysis is individual students, schools, or school districts. Mounting evidence also suggests that small schools and districts may generally produce superior results, once the effects of SES are acknowledged. There are many unanswered questions, however. For example, researchers have generally used state data, rather than national data, in their analyses.
States vary in the way they govern, organize, fund, and administer their schools and districts.
No one knows how such differences might influence student achievement. Other unanswered questions concern method and object of study. Although studies of achievement continue to offer a serious assessment of what students learn and what schools accomplish, they do not give a complete picture. In particular, they develop norms that may obscure the way small-scale schooling produces its effects. In the future perhaps studies of school effects, and of the ethnography and sociology of small-scale schooling may address some of these unanswered questions.