This study organized and applied an instructional strategy for preschool children, in a real-life classroom situation, with the aim of teaching them how to produce secondary from primary colours using different art materials. The research sample included forty children, mean age 4–5 years, in two kindergarten classes in Greece. The first group was a control and the second was an experimental group. This paper presents, analyses and compares the results of this educational intervention. A finding was that, unlike those in the control group, children in the experimental group worked indefatigably with great enthusiasm, learned to produce the three secondary colours and were able to employ this new knowledge in a variety of art activities.