There are 5 categories as you register as a special student.
1)Personal interest:maximum 6 credit per session.Cumulative total not to exceed 30 credits including this registration.
YOU DO NOT NEED OFFER ANY MATERIALS FOR THIS REGISTRATION.
2)Professional certification: Give the name of the association from which you are seeking certification.
3)Transfer of credits: Enclose a letter of permission or formal written agreement from specify institution.
4)UPGRADING:Hold a Bachelor's Degree from specify institution ( such as a degree got from China )
If you belong to this category, you must take the DEGREE CERTIFICATION with original seal to the faculties and you can register no more than 4 courses in one session.
5)Gifted student:Enclose a letter of recommendation from specify school.
Now,the tuition is 560/course for special student.You must register by fulfilling the form for special student EACH session and get every faculty's approval SEPARATELY if you take some courses from them.
PS. YOU CAN FIND THE FORM ON OU's WEBSITE.
Good Luck!