Tapered-point bamboo chopsticks make great filler for chewed-up screw holes in wood. Coat 'em with wood glue (or Elmer's), hammer 'em in as far as they'll go, then cut 'em off level with the surface with end-nippers or dykes or some such. (Fancy folks use flush-cut saws.)
If the hole is larger, you may need to trim some of the chopstick tip off to get the size of cone-shaped wedge you want. You want it to wedge in before it bottoms out.
Makes a really strong screw-hole plug.