At a TeachMeet at Anglia Ruskin University, we heard a presentation about giving students QR Code links to videos and other learning resources in advance of lectures to prepare them for what they'd be learning. Yes, flipped learning. But, in addition to flipping the learning, it was ensuring that the students knew what the content of the lectures would be.
So, for a couple of weeks now, when I've decided what I'm teaching, I send an email to my class to give them a brief outline of the week ahead. It takes about two minutes (if that):