In May of 2000 administrators completed the first stage of a carefully controlled, independent study of the effects of Core Knowledge in public schools in Oklahoma City, where 32 of 67 elementary schools have implemented the curriculum. The computer randomly selected the control students on these variables. In fact, however, the Core Knowledge students made significantly greater one-year gains in reading comprehension, vocabulary, science, math concepts, and social studies. The vocabulary gain was especially notable, since vocabulary is the single best predictor of academic achievement, and the area where the gap between ethnic and racial groups has proved to be especially difficult to overcome. Since vocabulary gain tends to be cumulative, it is expected that the magnitudes of these gains in equity and achievement will grow larger as the Core Knowledge students move through the grades.
Researchers plan to conduct further analyses and longitudinal studies in the future.
In 1999 a three-year study of Core Knowledge schools across the country conducted by researchers at Johns Hopkins University and the University of Memphis concluded that, when the Core Knowledge Sequence is fully implemented, it really works. The Hopkins study concluded that Core Knowledge provides students with a broad base of knowledge and a rich vocabulary, gives students the knowledge necessary for higher learning, and creates in many students a strong desire to learn more. Students retained the Core Knowledge content they were taught and were able to build on this content by making relevant connections. They also began to exhibit increased interest in reading. Core Knowledge also appears to improve the professional lives of teachers.