Before fine-tuning content for a particular session, I start out with a Google Form and a list of suggested topics (e.g. Google for Research, Nearpod, Kahoot, Student Projects with iPad, Workflow with eBackpack) that I perceive to be campus or department needs. Based on this initial feedback, I begin crafting pre-needs assessments for particular courses. Even within a workshop focused on a specific tool or technology, you will find both novice and advanced users, so that's where the pre-needs assessments really pack a punch.
In my last workshop some said they already knew it all. I should have been prepared with other assignments for them.