If other students are writing furiously, they are probably writing without a purpose. Make a rough outline to keep you on track. After outlining, write the essay, filling in the details. Be as specific as possible. Generalities by themselves are boring.
Details alone are just a grocery list.
Use your details to support a general context, and then draw relevant conclusions. When instructors ask you to discuss, they want you to show more than a knowledge of the facts. They want you to demonstrate a grasp of the relationships among the facts. They want to know if you see similarities, differences, or a cause-effect relationships. For example, even though you write a wealth of facts, you might fail a history question involving the Crusades and the discovery of America if you miss the cause-effect relationship.