user specific textfields – updatable

I am developing a wordpress site that essentially acts as a physical workbook would where students work through material and then have a Q&A section on our website. Ideally, students will login to WordPress, access the workbook section and be able to add answers into text boxes (or text areas) and come back and modify answers over several different sessions. Most of the WordPress plugin forms I see are only for submission to email or comments. Is there a plugin available or any way to have text boxes available for updating user stored information–other than writing my own plugin?