depends on the teacher
strat 1: put your phone behind the chromebook screen. make sure your desk is facing the teacher’s, otherwise they would just see
strat 2: putting your phone facing up against the side of your thigh away from the teacher. this is good for when your desk is not facing the teacher. but if you look at for your phone for too long using this strat the teacher might notice, so like do this time to time
strat `3: put your phone against a binder or something related in shape away from the teacher. the teacher MAY not see this but if the teacher reads hand movement you’re done
i hope this wording was alright, ill try to answer questions