This report contains the V, VI, VII of a series of experimental studies on the “Form-Color” problem.<BR>The experiment of study V was designed to investigate and compare the controlled instruction and the experimental instruction to the stimulus figures made in reference to the “figure of KATZ”. The stimulus figures used were geometrical figures, objective figures and abstract figures. These responses were respectively considered from a developmental point of view. The results were as follow. In the controlled instruction used the geometrical figures responses shifted from color to from between the ages 4-5 and 6. This result intensified one year later than the experimental results for the Lotto-Methode. On the one hand, when the experimental instruction was used the geometrical figures were already identifiable at age 4 and the form abstra-ction was more dominant than the color abstraction. In the controlled instruction using the object figures for age 4, the form abstraction was more dominant than the color abstraction. In the experimental instruction already the form abstraction was remarkably more dominant than the color abstraction in the age 4 group. In the controlled instruction using the abstractive figures, responses shifted from color to to form between the age group 4 and 5. In the experimental instruction the responses shifted from color to form between age groups 4, 5 and 6.<BR>Experimental study VI was designed to compare the results of the responses of the experimental group on the classification of fifty-four assorted cards. These involved geometrical figures, object figures and abstract figures. This comparative study shows the results of the responses to a groups of eighteen assorted geometrical figure cards. The results were as follows. In the case of the experimental group, the color classification was more dominant than the form classification in the age 3 group. In the age 4 group the form classification was more dominant than the color classification. In the older age group the form classification was consistently more dominant than the color classification. In the comparative group the color classification was more dominant than the form classification in the age group 3 and 4. In the age 5 and 6 group this form classification was more dominant than the color classification. In this group of classifying geometrical figures the responses shifted from color to form between the ages 4 and 5. In the older group the form classifying was consistently more dominant than the color.<BR>Experiment (VII) relative to pre-training the classifying of form and color, examines the effect of pre-training to the following abstraction of form and color. In the group which participated in the pre-training program the classifying of the color abstraction was more dominant than the form abstraction in the 4; 3 age group and 4; 10 age group, and in the 5; 9 age group, form abstraction was one hundred percent. On the other hand in thegroup which did only the pre-training of the color classifying the color abstraction was one hundred percent in the age group 4; 0, in the age group 5; 1 the color abstraction was more dominant than the form abstraction. In the age group 6; 0 the form abstraction was more dominant than the color abstraction. In the older age group the form abstraction was consistently more dominant than the color abstraction.<BR>From the above stated results it has been confiremed that in the study of “form-color” problem using the “figure of KATZ”, card sorting of form and color, and pre-training of form and color classification, the response to abstraction have to dowith the developmental conditions in terms of age. rather than with the individual “Eigentätigkeit” presupposing a temperamental character-ological being.