Attach a paper clip to plastic spiders and put them in a tub of water. This can be done by threading one end of the clip through a leg or the body. Make a fishing rod by attaching a magnet to a string and tying the string to a pole. Each child get a chance to fish out a spider. Paint colored dots on the spiders with certain colors tied to special prizes. For example, spiders with white dots might get to keep the spiders. Red dots win candy bars and a very special blue dot wins the grand prize.