The purpose of several studies was to examine the effects that differentially coded (black and white or color) illustrations had on students who were classified as field independent, field neutral, and field dependent on tests measuring different educational objectives. The effects of visual and verbal test formats were also examined. In general, results reveal an insignificant interaction between coding type and level of field dependence. However, field dependency was found to be an important instructional variable, and, for some types of learning objectives, the process of color coding instructional materials may reduce achievement differences attributed to differences in cognitive style. Unexpectedly, students who received verbal tests across all field dependence levels achieved significantly higher mean scores than did those who received the visual test formats. (Author/MES)