@CourtneyCrawfor - I notice that the Highlight functionality doesn't work in Student Preview mode. Nor do Notepad and Sticky Note. The Student Preview defaults to showing text to speech, dictionary tools, and all the tools except highlight, notepad, sticky note, and Desmos calculators. I do not see any way to enable those for the Student Preview; I could be wrong, but I've tried a variety of ways. I think enabling those is a good suggestion.
Additionally, be aware that although many tools and accommodations, including text to speech controls, display in Student Preview, all of those tools and functionality will not necessarily be available to your students. During the actual testing, the system will use whatever tools and accommodations you've enabled for an individual assessment or at the tracker level or at the student level. For example, if you don't enable Ruler for an assessment, then it won't be there for students, even though you see it in the Student Preview. I think you need to log in as one of the students to see the experience as it will actually be.
Jen
