The World Institute of Computer Assisted Teaching (WICAT) system was installed in November 1985 at the Salina and Fordson Schools in Dearborn, Michigan, and selected students in grades two, three, and four received their regular reading and/or mathematics instruction in the WICAT computer laboratory. Achievement gains of these students were measured using the Metropolitan Achievement Test (METRO), the Iowa Tests of Basic Skills (ITBS), and the Michigan Educational Assessment Program (MEAP). Analyses of the test results indicated that students who had received WICAT instruction had significant achievement gains in mathematics and reading. The percentage of grade four students mastering reading skills increased from an average of 42.2 before WICAT to 51.2 after WICAT, and, in September 1987, 60.5% attained mastery. The average mathematics gains for second grade students increased 150 percent from a gain of 8 months to a gain of 12 grade equivalent months. Gains in third grade mathematics increased 143%, from 7 to 10 months. Low achieving mathematics students benefitted the most from the WICAT program, with gain scores of up to 14 months during one school year. One-year ITBS reading gains remained the same as before WICAT with gains of 8, 8, and 10 months respectively for second, third, and fourth grade students. Three-year METRO/ITBS mathematics gains were significant for grade four WICAT students when compared with the gains of similar non-WICAT students in other Dearborn schools. The test scores and other evaluation data are displayed in eight tables and in extensive appendixes. (EW)