Does that seem weird to you?

In my dyad placement there is a high spectrum autistic boy, we'll call him Sam. This is a second grade classroom and the kids are getting to that age where some of his unusual behaviors are beginning to stand out. What I was told by the teacher is that in kindergarten and first grade some of these antisocial behaviors don't stand out as much, but as the children get older the behaviors begin to stand out.
His therapist and parents are asking for us to help them implement this technique where they label the behavior. When Sam does something antisocial the therapist and parents give him a red stick and say, "That's weird." The teacher told us that the parents and therapist have told her that this is having good benefits for Sam and they want us to do it in the classroom. We wouldn't be handing out red sticks, but if we saw him doing something antisocial we would walk up to him and say, "That's weird."
I'm not sure how I feel about that. Far be it from me to argue with this kids parents and caregiver, but the way we are being told to say it gives me pause.
I'm a big believer in the idea that it is not what you say, but how you say it. I'm wondering if this is the best way to let Sam know that this behavior is unusual.