I've used my pencil to tap my hand in class, or to count my fingers

As for the nose check, I make it look like I'm going to rub the bridge of my nose (like what some people do when they're annoyed) but slide down and do a quick inhale

I wish I could be more aware in class, but I have to listen to the teacher. I can't be counting chair legs or people legs, or whatnot, lol