Which school does does your child attend? Hopefully I can direct you to the right site for I do not have access to student grades.
Student grades can be accessed through the PowerSchool Parent Portal. PowerSchool's Parent Portal provides real-time access for parents to their child's grades, attendance, assignments, and more.
Our KnowledgeBase article on how to access PowerSchool Parent Portal should walk you through the steps to log-in to your account. I have provided the link below.
How do I log into PowerSchool? How can I find my account information?
If you do not have access to the link of your district's PowerSchool Parent Portal, I recommend reaching out to your school district who should be able to provide the necessary information.