For those using SimBio's modules as in-class teaching tools, we recommend that you have your students register online and subscribe to the SimUText for your course before the first class period for which they will need access. That way, any technical and/or financial problems can be resolved by the student in advance, in consultation with SimBio's support staff. Students can submit a support request at http://simutext.zendesk.com.
One way to encourage student compliance with subscribing in advance of class is to create an assignment that is due before that class. For example, you might create an assignment that includes the first section of the first SimBio module you'll be using and set a due date prior to when that class meets.