He wasn't being very subtle about it.
All I did was to meander over to where Antoine and his two friends were giggling when Antoine exclaimed a few expletives when he saw that I was paying attention to him.
But I hadn't seen the cell phone yet.
It wasn't that long after that I took another stroll and spied Antoine watching some video on his phone. I immediately went in for the confiscate.
He refused to give me the phone. He said he'd go to the office. I had no problem with that and let him go.
He returned about fifteen minutes later with a pass back to class. And I thought nothing more of it. Until I meandered his way again and noticed a cell-phone-shaped bulge in his pocket.
So, when I had a moment I asked the office staff about it.
The secretary remembered the boy. She said he'd gone "behind closed doors" with the principal. But she was the one who was supposed to confiscate cell phones, so something was off. She went to the principal, and the principal said that Antoine had asked to talk to him about his credits.
Clever. And he would have gotten away with it too if I hadn't followed up.
But now administration knows why Antoine was really sent up to the office. (And I know in future to call the office and let them know a "cell phone violation" is on his/her way up.)
And Antoine? He gets the next punishment on the matrix, which is decidedly worse than having his cell phone confiscated until his parent can come and pick it up.