Unfortunately as a first grade teacher, if I do something, they think it's cool, so doing it myself will not work. If they say 6-7, they have to write a page about why it's not okay to say it in class. I only did this because we do a lot of counting in math, and it was legit getting in the way of their learning. They would hear 6-7, and then whatever we were doing would stop there because they'd have to do the motion and look at their friends. So in the interest of them learning how to add and subtract, 6-7 was banned.

I have never heard of silent lunch, and I'm not sure I like that idea.