A study developed a multiple regression prediction equation for each of six selected achievement variables in a popular standardized test of achievement. Subjects, 42 fourth-grade pupils randomly selected across several classes in a large elementary school in a north Florida city, were administered several standardized tests to determine predictor variables of vocabulary, general information (prior learning), arithmetic, word recognition, and listening skills. The dependent variables (reading vocabulary, reading comprehension, language total, math total, science, and social studies) were measured using subtests or combinations of subtests of the California Achievement Test, Form E. Data were processed by computer programs and yielded mean scores, a correlation matrix, multiple correlations, and regression prediction formulas for each dependent variable. The multiple correlations obtained ranged from a low of .77 for reading vocabulary to a high of .87 for mathematics total. Each regression equation also had its own constant. Suggestions are offered for improving students' word recognition skills, listening skills, and the quantity and quality of their stores of vocabulary and general information. (Three tables of data are included; 23 references are attached.) (RS)