A whip bow is a variation on the conventional bow and arrow. Both bows shoot the same type of arrows. Though the whip bow is less accurate, it is easier to make.
The whip bow needs a light sapling, such as hickory or elm, about 3 feet long and 1/2 inch in diameter, and 3 to 4 feet of good heavy string or cord.
Tie one end of the string to the thin end of the stick. You may need to cut a groove in the stick to hold the string. Make a fairly large knot in the other end of the string.
The arrows can be made out of virtually anything and can be round or flat and any shape desired. Their only requirement is that they have a notch about one forth of the way down from the pointed end. Children would usually just use sticks or sometimes large weed stalks such as horseweeds. An arrow will take a straighter course if it has some fletch-ing such as feathers on the back end. Cedar shingles make good arrows.
To use a whip bow, put the knotted end of the string through the notch in the arrow. Hold the end of the arrow in one hand and the end of the stick in the other. Whip the stick forward, releasing the arrow simultaneously. As the arrow flies forward, the knot slips out of the notch, sending the arrow forward with great speed. The whip bow has all the force of a bow and a sling combined.
(copied from
http://thelibrary.org/lochist/periodicals/bittersweet/fa82f.htm)