The advantages of coloring pages:
1) Self expression - coloring on a blank "canvas" (notepad), is a method for children and grownups alike to reveal themselves. You can tell a lot about the method an individual is feeling by the images that they draw, the colors that they use, etc. It is very important to provide children a possibility to reveal themselves, and not all children reveal themselves through words and through writing, many usage art.
2) Color recognition
3) Therapy - for many individuals (myself consisted of) coloring is healing. Despite whether it's scribbling, or coloring the "finest picture ever", coloring can be a method to de-stress, after a busy morning of school work, unwind, and calm down, after the stresses of a day at school or work.
4) Grip/Control - many children learn how to hold a pencil, pen, marker, or colored pencil, by first learning how to hold a crayon. The little muscles required for penmanship later on begin to be developed while coloring.
6) Structure motor skills
7) Focus - Focusing on a single job for a length of time is required for coloring and for all sorts of things throughout one's life.
8) Limits - Another thing that children learn from coloring pages, with preprinted images on them, is how to accept limits. While a toddler or preschooler may doodle all over a coloring sheet, without any respect for the limits (lines on the coloring page), as the kid ages, they will begin to appreciate those lines, and make an effort to color between them. While I motivate blank paper coloring for free expression as frequently as possible, for many preschoolers pre-printed coloring pages are their first exposure to printed limits. This early exposure to limits in print, will be a huge assistance when handwriting time occurs, and the kid needs to appreciate the limits of the preprinted handwriting lines on the paper.
9) Turning point - This is the last little "importance" of coloring that I will point out in the meantime, and that is that coloring in the lines is a milestone, a sense of accomplishment, the primary step towards an effective scholastic career for many children. For many children coloring in the lines is just as important as counting to 10, counting to 100, reciting the alphabet, finding out the reproduction facts, etc. It's a milestone that says "yes I can" do whatever I come across, and it provides children with pride, a sense of self worth, and helps them to feel accepted in a society that is frequently fast to judge, and slow to respond. This sense of accomplishment will carry them through life, and help them not to quit so easily, when something brand-new comes along.