There are two hourly exams during the semester, currently scheduled for weeks 5 and 11. There will also be a final exam, which is cumulative.
The best way to prepare for the exams is to be familiar with all the stretches and text problems done in class, as well as the homework assignments. Many exam questions are related to the work done in class and in the homework assignments.
Each individual instructor will provide you further details on Exams throughout the semester.