Interactive Workbook

We have a training program where trainees work independently on a workbook with questions and they research and type in their answers, in preparation for an in-person review session before a certification test. We are currently doing these in Word, then save as a Pdf with text boxes for them to type in.  What tool would we be able to use to replace this process?  We would much rather use something online that saves answers and is easy to get to.  Any ideas?  We looked at Rise and that wouldn't work with the open text boxes.  Storyline makes it really cumbersome as the questions would have to be across different slides.