Collect a large cardboard box either by asking parents to donate or searching behind a grocery store. The box should have a long, rectangular shape similar to a horse body. Cut off the flaps on one side of the box to represent the front of the horse and tape the back flaps closed. Sketch a horse head shape on a square of cardboard and cut it out.
Allow the children to paint the entire box and the head shape using nontoxic tempera paint. Ask the children to cut long strips of yarn for the mane and tail. Children can glue the yarn around the head piece as a mane and onto the back of the large box for a tail. They can also glue a button or googly eye onto each side of the horse's face along with two ears cut from construction paper.
Cut a small slice into the back of the head-shaped cardboard. Slide that opening to fit into the top edge in the front of the large cardboard box. Put the cardboard box horse on a rug in the classroom and allow children to use it for dramatic play. They can pretend to feed, ride, and groom the horse during center time.