He would not be able to talk, but mr Catz would start smashing things, ripping up curtains and backpacks, and would probably be fired on his 1st day, if not, the 2nd, 3rd, 4th, 5th, 6th, or 7th.
If he was smart, he would teach kids about Science, this is due to the fact that he fits in with science, along with other species, plants, and other stuff. So if he WAS smart, then he would not do the things that a normal cat would do.
“Greetingz, Studentz!” ~Mr. Catz 2019