The class has issues an difculties keeping on task during an independent worksheet, even with teacher walking around and monitoring. There is little to no improvement even with the teacher stopping and going over what the rules are and what they should be doing.
It could be that the assignment is too difficult for the students or it could also be that the assignment was too easy given the opportunity that allowed them to do their worksheet fat enough so now they get to do whatever they wanna do. While it is nice to do individual assignments in class as it testes their knowledge perhaps you can do like a full group assignment on days because then you are actively prolonging the activity for everyone because it is whole group rather than having everyone just do it individually.
I like the ideas of the dividers or going along as a class.