Materials:
stiff paper (ex: cardstock, postcards from the mail)
scissors

Step 1:
Start Drawing lines for where to cut and fold the basic body of the paper horse. To start with you will want a rectangle that can be divided into three equal parts with a width that is a third of the size of the body.
For example, we made a rectangle that was 9 inches by 3 inches. Lines were drawn for folding at 3-inch increments. Then lines for cutting the legs, head, and tail were made at 1-inch increments along the short sides.

Step 2:
Cut out the rectangle. Then, cut along the lines for the body parts. Finally, fold along the body lines.

Step 3: 
Now comes the part that makes the toy work. This is also the part that may take several tries to get right. The feet need to have a slight curve cut into them to allow the horse to rock.
See the picture for help.

Step 4:
Now, it is time to test it. Make a ramp out of a book, board, or some smooth surface. Place the horse on the ramp and see if it walks down. If it works GREAT! If not try going back to step three or attempt other changes. Keep working at it and don’t get too frustrated. Science is all about failure.

Step 5:
If one is working try making changes to the design and see if differences in the size of the legs, head, tail, or body have an effect on the toy.