Thanks to colorings the child perceives the world pattern, implements its own color discoveries. If a child paints the picture in unusual colors, you should not abuse him for that; it is his own opinion.
Images for older children may already contain small parts, complex narrative compositions with greater color palette. The outline is more subtle. These can be supplemented with coloring tasks. For example, to write the missing word, or paste a sticker, finish drawing, connect the dots.