You can find the color wheel and some aspects of color theory in two worksheets in English language, ready to be completed with crayons. This work is suitable for pupils of grade 6th or for primary school, for a first approach to color theory. The color wheel can be completed entirely using only the three primary colors, and the students can clearly understand the mixing of colors without using paint or watercolors, but simply overlapping the colored pencils. Here is the video tutorial on the use of worksheets:
Another worksheet is about achromatic colors (black and white), warm and cool colors, with three small drawings to complete with these topics. Finally, a brief exercize about complementary colors and their position on the color wheel, that introduces the topic of the contrasts and the use of complementarity in art and visual communication. The worksheets can also be found in Italian here.
color wheel : TERTIARY COLORS