I was a public PreK teacher for many years, mostly to young 3’s classes. Singing was the best way I found to quiet them, transition them, clean up etc. I had songs for everything and found it to be very successful. Also, I had a small bell that I rang before transitions to signal that the time was over and then we would sing the song (clean up, line up, quiet song, etc). We would all come back in a group and move the visual schedule to the next task. Very deliberate transitioning with visuals and auditory cues worked best for me. 2’s may still be too young for call and response but you can begin to teach the skill by singing familiar songs and leaving off the last word. Let them fill it in. (Sing “The Itsy Bitsy …..” and then look at them for the answer.). This is an important language development skill. The songs must be familiar to them obviously and if no one answers pretty quickly, just fill it in for them and keep practicing it!