Retrospective on educational testing and assessment in the 20th century

Over the last 100 years, the ever-increasing demand for testing as a measure of educational reform has created a very profitable market for the US testing industry. We follow the growth of this market since the 1900s in two different, but related, ways. First, we discuss some of the technical developments that have encouraged the use of standardized testing in general and contributed to the growth of the commercial testing industry. Second, we attempt to quantify the expansion of the testing marketplace during the 20th century by tracking several indirect indices of growth over time. We conclude that although technical innovations may have contributed to the growth of the US testing marketplace, they do not necessarily lead to better tests or better outcomes for those who use them. There is a need to more carefully monitor the effects of these tests on teaching and learning in general, particularly when the tests are used in high-stakes contexts.