Under the form’s Submissions button, you see the following buttons:
List Parents button
List Students button
Click the 'List Parents' button to see which parents have submitted the form and which have not. Specifically, to view the list of parents who have not filled out the form, select “No submissions” from the drop-down filter.
Click the 'List Students' button to see which students have a form submitted on their behalf by a parent/guardian. Select “No submissions” to see the students whose parents have not filled out the form.