"Miss Brown, he said that I was dumb."
"Miss Brown, she said that my picture looks ugly."
"Miss Brown, he said that I stole his scissors but I didn't."
My response is usually not what they're expecting...
Me: "Do you think your picture is ugly?"
Them: "No."
Me: "I don't think it is either. I can tell that you worked hard on it. So, I know that, and you know that, so let's not worry about what so-and-so thinks."
And then I give them that million dollar, first grade teacher smile and send them on their way.
Yes, I want to teach my students to say kind things to each other, but I also want my students to learn that it doesn't really matter what others think about them.
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Why do we get so bent out of shape when someone doesn't think well of us? I think, for us, it's mostly a matter of pride, which is understandable. Nobody likes to look dumb or incapable or viewed in a negative light. But why do we give so much concern to what they think? They're not in our heads. They don't know the whole back story. They don't know where you're coming from or where you're going. They don't know what your intentions actually may have been. They're not you and they're not God.
With my students, they care so much about what their classmates think but their peers only see a small part of who they are. As their teacher, I know them all so well. I know what they're working on, what their skills are (or aren't), what their tendencies are, where they started, and where they are now. I am a much better judge of whether or not their picture is pretty or if they're good at math because I can see a much bigger part of who they are.
So really, if you're trying your best and doing what you can, if you feel good about it and know that Heavenly Father is pleased, then that's great and that's all that really matters. Go to your happy place and don't worry about what others think.