A marketing essay requires that a student effectively and completely applies the material imparted during the class. This is no different from any other topic or course in college. A marketing class may focus on the overall theme of marketing or may hone in on individual aspects of this broad domain. Either way, the material must be applied appropriately and accurately.
Many marketing essays for college classes entail solving some kind of potential real-world dilemma or situation. For example, a paper might ask that students create and develop a full marketing plan for a new business, given specific budget constraints and objectives. It's important to not only apply broad concepts, but to specifically plan individual steps of action, solutions and components.
Marketing classes in college are often loaded with terminology and specific concepts. Professors want students to use these specific ideas and terms, and to use them correctly. This will help show that you understand and can apply the material, while taking your work a step farther by displaying the correct usage of specific terms, ideas, themes and concepts. From SWOT Analysis to web 2.0 marketing or anything in between, deploy the terms and concepts that were covered in class.
The best classroom for marketing in college isn't the study hall, it's the real world. Everywhere you turn you can see businesses and their marketing successes or misfires. Using real-world examples will demonstrate that you not only can read and write about the subject, but that you can recognize it and make connections about it in actual life and business, which is ultimately what any student will need for their career.
It's not enough to talk about vague real world examples or concepts. Instead, citing valid resources will help you make your point more effectively. Knowing that McDonald's has huge sums of money tied up with international marketing campaigns is one thing, but being able to cite specific figures and dates makes your case that much stronger and more complete.