With regard to the original post, its zero tolerance policies that are enacted at a local level. This means zero fun and zero flexibility. They think that suspensions and punishments for small infractions of any reference, pretend play, or jokes about some topic they don't want kids to learn about (guns, smoking, etc.) will help stop kids from growing up in a culture of violence, drugs, etc. and stop them from thinking about those topics. Instead it doesn't stop it and the kids get screwed over from missing school and possibly having their confidence stunted.
In short, its kind of like the same logic as the drug war, trying to give more punishment for minor rule breaking to stop whatever they want to stop. Its had similar results as well. (Obviously not trying to compare the two directly, as the drug war is far more serious and large scale, just an analogy)