No. If you do that, they will not study anything since their notes will be their crutch. Instead, make it clear that cheating will be grounds for an immediate 0 on their tests. Also, what you can do is, on test days, have them leave their book bags and pocketbooks at the door except for a pen or pencil, and if they have computers on their desks, tell them to either put the monitors on the floor (for the flat screens) or turn the monitors so that the back of it is facing them. However, this is most effective if it is implemented at the beginning of the semster instead of in the middle.