Books! Oh, books!!
Stacks and stacks of books!
Treat them with respect, or else. They will find retribution.
P.S. When I taught, there were always boxes of books in my classrooms. One time I went to a book warehouse, where boxes and bins of books were stacked for people to sort through. I found myself in huge boxes, where I nearly disappeared. Bought many many books for my students and the school.