A child student can be moved to a new Family in Teachworks by editing the student's profile, selecting the new family using the "Family" field, and submitting the form. You can do that by following these steps:
1. Go to Students > Students > Edit (the little pencil icon in a the student's row on the Students table).
2. Use the "Family" dropdown menu in the "Family Information" section to select a new Family for the student.
3. Submit the form using the "Submit" button at the bottom of the page.