Lesson

Hi all. Here's a beginner's question for you. Please be gentle:
The box within which the text is displayed on my students' account is smaller/thinner than the box within which text is displayed on my teacher account. This results in the last part of the Question Page getting cut off from the students' view; my students don't see all the text.
I'm not sure which version of Moodle I'm using, as the person who installed it is unavailable to me, but I know that the version is somewhere in the 1.5.somethings. Does anyone know if this has been a common problem with any of those versions? I've found nothing about it in the literature or in recent posts. If so, any ideas on how to fix it?
I really appreciate your help.