When writing the essays for the unit tests, use all the help you can get. Use flashcards,notes,high-lighted parts of the textbook, and use some of the crash course videos. Being specific with writing the essays is the main thing to stick to, also being formal and simple is highly recommended. Writing essays about widely ranged topics in the class can be very hard, which is why it is important to understand all the content before-hand. The essays are significant and vital to your grade so it's important to answer all the parts to the best of your knowledge. Writing the essays may be the easiest part of the test but it can be very difficult if not a topic that you didn't study or didn't acknowledge the information.