Students know that magnets have two poles (north and south) and that like poles repel each other while unlike poles attract each other.

As noted in the Content Tip for Physical Science Standard 1b, it is technically more accurate and potentially less confusing to use the terms north seeking pole and south seeking pole rather than the terms north pole and south pole. However, for convenience, the shorter terms are often used. Irrespective of the terminology, poles that have the same magnetic charge repel each other while poles that have opposite magnetic charge attract each other.

Magnets have the amazing property that if you break a magnet in half, you will now have two magnets, each with its own north seeking pole and south seeking pole. If you take two bar magnets (i.e., start with four different poles) and put them together end to end so two opposite poles attach to each other, you now effectively have just one bar magnet that, while it is longer, has only two poles (compared with four at the beginning). At the Grade 4 level, you should not try to understand or explain the physics of this phenomenon.