Art = 1 the expression of creative skill through a visual medium such as painting or sculpture.
2 the product of such a process; paintings, drawings, and sculpture collectively.
I took art at school
My art was not very good
Arts = 1 the various branches of creative activity, such as painting, music, and drama.
2 subjects of study primarily concerned with human culture (as contrasted with scientific or technical subjects).
At university I studied the Arts, and liked music best.
Arts and Crafts= the arts of decorative design and handicraft
Basketmaking would come under the heading of Crafts.