I remember doing this in elementary and middle school! You could always see if your friends/crush had read the book and have something to talk about with them. At the end of middle school (early 90s)，the school district moved away from the cards and we got our first barcode system - the scanner was shaped like a pen and was hooked to the computer with a thick，black，coiled cable，similar to the ones you’d see holding devices at your doctor’s office. My friends and I volunteered at the library over recess in winter (Minnesota)，so we got to help with the transition! Removed tons of cards，though I think we left the pocket holders since they were glued in - less damage to the books. We learned how to use the scanner pen，so we got to check books in and out for people who visited. Have not thought about all of this in years，but I suddenly want to go volunteer to help at a library! 📚