Show that the ends of the rods will attract both the south and the north poles of the compass (random magnetic domain orientation).  Hold the rod on the north/south line and dip the end pointing north to an angle of 60 to 70 degrees and hit the end about 20 times with a hammer.  As you bring the rod to the compass it should attract one pole of the compass and repel the other (oriented magnetic domains).  To randomize the rod again align it along the east/west line and hit the end about 20 times with the hammer.  If you have a cement floor, you can just drop it onto the floor several times.  

If you have trouble randomizing the rod after magnetization, you can use the High Power Video/Audio Tape Eraser that can be found with the Science of Sound tapes in the Oscillations/Acoustics Section.