Stupid people with smart phones.
When i was in college getting my engineering degree, our department chairman had several laws that he would mention. (name withheld)'s Law #2: The worst math students will have the best and most sophisticated hand held calculators.
i miss those days before cell phones, the internet and the Windows Operating System. Fortunately i kept all of my old text books so that i had the information in hard copy to teach the next generation after the zombie apocalypse has come and gone.