Management is both an art and a science. To me, science is about following rules. There are some rules that can be followed in management. Art is about creating. You do need to create to be a good manager. You need to balance the two, but begin with a little of both.
I like #5's thinking process. Management, at least positive management, involves skills that can be applied in the areas of science and art, but many other kinds of abilities and techniques are also required. As a function of relating to and working with people, I think it's very appropriate to classify management as a social science.
While I agree that management has both art and science in it, from my experience, the best managers are those that have an inborn intuition/art on how to handle people.
From what I have witnessed, the science aspect of management (IE: inventory control, etc.) can be accomplished by most people with enough training, however one has to be a skilled communicator and have a keen insight into how different people are motivated/tick in order to effectively manage them to perform as you would like them to.
It's clearly both. There is a part of management that is scientific. This is the part that deals with things like maintaining the right levels of inventory or ordering inputs to be available "just-in-time" to reduce warehousing costs. These are scientific because they are quantifiable.
But there is also an aspect of management that is an art. That is the part where the manager has to work by feel with each employee. The manager has to understand how to treat employees as a group and each individual employee. If the manager does this badly, workplace morale can suffer. This is an art because it is not quantifiable.
This is a very good question, and a good one for a debate.
Management, as a field of study, is often classified as a science. The reason for it is because the field involves and requires enough research to identify which are the best practices to conduct within an organization in a leadership position.
Another reason why it is classified as a science is because there is a specific methodology involved in the process of hiring, firing, limiting, modifying, and implementing both personnel and new programs. Usually the methodology that is required to manage a small or a large corporation is quite clear-cut and repetitive. This alone may qualify it as a science.
However, it is arguable that Management requires art in the form of visibility, marketing, symbolism (logos, mottoes, tag lines), not to mention the need for creative ways to empower and motivate employees. All this involves artistry, charm, and charisma: Those latter elements are hardly scientific, but are just as effective as the elements that are.
In all, management is a combination of leadership, research, and productivity. In turn, a successful result can only be possible with a combination of research-based best practices and the inclusion of artistic features such as good marketing, attractive symbolism, and high visibility.
I think it's niether. It's certainly not art, not in the true sense of the word. And while it uses some techniques that are based on maths, but it doesn't use the scientific method so it is not really a true science. Mostly, management is about dealing successfully with people, so maybe it could be called a 'social science'.
(If you attend a management course at university, it won't be organised by the science department, and it certainly won't be organised by the arts department :-))