Mathematics graduate students who are completing their degree program this Spring should follow the steps as outlined in the Graduate Handbook. (For MS, refer to 5.1.G on p7, for PhD refer to 5.2.J on p10, in the 2017-18 Handbook). Here is a reminder of what to do as concerns your final exam (the defense). People and room calendars fill up quickly in this busy time, so plan and act early.
Work with your major professor and committee to schedule the final exam (reserve 2h), reserve the room online, and schedule it with Graduate School (two weeks in advance). For all these, you can find links at https://gradschool.oregonstate.edu/progress/exams-and-meetings (You should also file a diploma application and know how to format the thesis; see https://math.oregonstate.edu/grad_resources for more links).
For PhD thesis, MS Thesis, and MS Paper options, your defense includes a public portion which must be advertized. Send the necessary information including title/abstract of your presentation to Graduate Coordinator, Joy King. Your defense will appear as an event on department calendar. It would be best to do this more than a week in advance so the potential attendees can plan ahead. (You can invite anyone to your defense).
For MS Exam by Qualifying exam option, you still have to have a final oral exam with a committee present. You are also required to make a presentation, which may be scheduled at the time of the final exam; it could also happen at a seminar or other venue that your committee approved. If this happens at the exam and you plan a public presentation, make sure you advertize the same way as in Thesis/Paper options. Otherwise, inform Graduate Coordinator of the schedule of the exam.
Your adviser and committee will fill out the paperwork that will be sent by Graduate School, and the Graduate Learning Outcomes rubrics https://math.oregonstate.edu/ms-learning-outcomes and https://math.oregonstate.edu/phd-learning-outcomes