We recommend that your child create the account or that you create it together. Only one account can be tied to your child's official College Board record, and it's important that they be able to access the account.
In other words, if you create an account without your child's input and register them for the SAT, and they later try to create another account to see their scores, they'll be blocked from doing so.
Make sure the child has access to the email provided for the account in case they need help signing in.
Create a College Board account
More Parent Resources
Parents Guide to SAT
Parents Guide to AP
Parents Guide to Financial Planning