I have 2 children using different devices. do I merge them or do I have to keep their grades separate
Don't merge them.
It will combine their records as 1 student, logins, enrollments, and grades will all be linked to 1 user.
Since you have 2 students, leave them unmerged, and let them login separately.
You are most likely getting this message because you are using the same email address for both accounts.
You can change the email address for the students, or if your school is importing them for you, you might have to update the contact information in the SIS. I'd talk to the school first.
How do I change my default email address in my user account as a student?
Merging doc with warnings, How do I merge my user account with an account using the same email address as a student?
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