"I've noticed that the presence of the pockets make them comply. I haven't required that they put them in, I just said that if I see them out, they will go there. I've only had one infraction so far. I tell them that it goes "in your pocket or my pocket (wall holder). They get it. They've just been looking for a reason to conform. Kids..lol."
"I gave tickets every day for the first 4 days to every kid who put their phones and chromebooks away without being reminded. Then I gave tickets on random days by pulling phones out of my box. Next week I will start "charging" tickets whenever I find phones or chromebooks out. It takes a while to build new habits, so I'm trying to use intermittent reinforcement to help."
I know of one teacher who taught students to recognize appropriate times to use technology by establishing a Red/Yellow/Green "zone" in the classroom. Red = no devices. Yellow = you may look briefly. Green = now is an acceptable time to use technology freely.
Have students rank themselves visually before or during your lesson so you know how much you need to differentiate.
Give students stoplight colored cards to indicate how they are doing on work. It is quiet and cheap.