To add your children to your account, simply go to your profile and click on Accounts. Under "Family Member Accounts", you will see a button that says "Add New Child".

If you'd like them to have their own Login, simply enter their email address. They will choose their password after their first Login,

If you enter their phone number, they will receive text notifications regarding the pages/courses/groups the follow. They can control their notifications under "Notifications" under their profile.