The registration worksheet allows you to enroll to the maximum course credits allowed by Academic Regulations, which for Yale College students is 5.5 course credits. If you have a need to enroll in more than 5.5 course credits, you will need to speak with your Residential College Dean.
If you add additional credits to your worksheet, you will not be enrolled in the courses without permission and will not see a black checkmark which indicates enrollment in the course.