If a child is gifted in art, schools should help to enrich the gift. Howevever, elementary teachers already do a great job of incorporating art into their instructions. Children learn early to color within lines, use appropriate colors, follow directions while coloring, choose colors to create, draw and color (create their family, pets, meals, clothes, etc.), water color on paper, finger paint, color shapes, and hundreds of other actitivies that become more challenging as the child moves up the levels. Teachers use these art forms to teach math, writing, reading and many other skills.
Older children are encouraged to participate in illustrated writing contests; poster contests; school, district, and state reading and science fairs. When the child is in high school and college, if the interest is still there, he can take art classes.
Many schools from the elementary level up have access to special programs, even specialized schools, that they present to students and parents when a child is gifted in the arts and sciences, for example. I think that many schools, along with parents, are doing a good job of using needs assessments, interest inventories, and other tools to help plan a child's educational program.
Art classes may be a waste for some, but schools must consider each child's special gifts and needs, and build on that. Students and parents who are not interested should not be forced to take art classes that are given for the sake of becoming adept in the art of creating works. On the other hand, all children need to learn some art skills--shapes, for example, could help them in math, chemistry, science, etc. So, a lot of common sense should be used in making these decisions.
I suppose someone who is interested could research a little, and make a hub. If I cross your hub, I will read it!