As a current (and older) student I completely understand your frustration. I am amazed at the actions of my fellow students during clinicals. The texting, breaking, looking bored/yawning and..... sleeping. Yes, there was one student that slept at the desk all day while I never sat down. Apparently, this was his MO throughout the clinical rotation. No preceptor had ever told our instructor that he was disrespectfully slacking during every clinical. Finally, another student got fed up with his embarassing behavior and told our instructor. She dealt with it swiftly. It is an embarassment to the school to have this going on.
If you do not want to confront the students directly here is my advice. Tell the instructor that as a group you feel the students are not coming to clinicals prepared and that they are violating rules (texting, etc) during the clinical. If you are not the manager of the unit, then have the manager give the instructor a list of expectations during the clinicals. Many times our instructor would tell us "This unit has high expectations. They expect initiative, they will ask questions, they expect you to jump in and participate. This unit is eager to teach, but they expect you to be eager to learn". She knew what every unit expected and would give us a good talking to before we went to that unit. If you have made it clear what is expected, then the students are asking to be "schooled" (as my classmates call it) if they do not deliver.
Alternatively, you can just have a talk with the student at the beginning of the shift and let them know what you expect individually. As a student it is sometimes hard to read your preceptor.... does she want me to jump in? Does she want me to wait to be asked? Does she want me to follow her every step or does she want me to back off????? All questions that we wrestle with in our heads. The absolute best day I EVER had was when I had a seasoned ICU nurse meet me eye to eye at the desk. She said "I'm glad you are here today. This is how I work. This is what I expect from you. I am here to teach you anything that you want to learn, but I will not beg you to follow me and get involved. I would love to have you right beside me all day long, but if you just want to sit at the desk, I'm not going to come and get you. I would love to show you how to do procedures, but if you don't want to try, I'm not going to beg you". She scared the crap out of me, but I knew exactly how it was going to be up front and I learned a ton! It was a great day!
I know that NO ONE should have to be told to stay off the cell phone
and not go down to the cafeteria for random breaks for arbitrary lenghts of time. However, some of my fellow students had to be reminded and some were even put on contract (not a good thing) for repeated offenses. Just include that in your morning talk. "Texting while in the work area is not allowed. Please do not that until our scheduled break time." Students are used to being told what to do. I don't think it will be offensive if you just lay out the rules at the beginning of the day.
This is just a student perspective!