How to run a single scala worksheet in a scala project?

Within a Scala project, I inserted 4 worksheets in the src directory. I realized however that when i run a worksheet, actually every worksheet is runned (I noticed that from my worksheet I can access to the classes of the other worksheets even if I didn't explicitly run them before). What I would like is to run only the worksheet I opened and not everyone in the same project. How can I do it?