Export diary for multiple classes

I work in student support with lots of 1-2-1 classes. I want to export the diary for each of my classes. At the moment, the only way I can find to do this is to manually go into each class and export the diary to .PDF

Is there a faster way? What would be great would be to select multiple classes and THEN export which would generate one file per class.

There isn't a faster method for the diary but
if the planner's format works for you, you can use that PDF instead: Planner view > Export > PDF