A student stuck a note on his classmate's back while they were at recess (课间休息) one day. The note said "I'm Stupid". He asked the rest of his classmates not to tell the boy. The other students started laughing at the boy, but wouldn't say why.

Soon, it was time for their afternoon math class. Their teacher wrote a difficult problem on the blackboard. No one was able to solve it except the boy with the note on his back.

Ignoring (忽略) the laughter, he walked toward the blackboard and solved the problem. The teacher asked the class to clap for him and took the note off his back. She told him, "It seems that you didn't know about the note your classmate put on your back, but you didn't seem to care anyway."

Then the teacher looked at the rest of the class and said, "Before I punish you all, let me tell you two things. First, all of you will be labeled (贴标签) at one point or another by other people who don't want you to succeed. All you have to do is ignore these labels. You have to take every chance you have to learn, grow and improve. And it seems that none of you are friends with this boy, since none of you were kind enough to tell him about the note. If that's true, then you'd better hope that you have some good friends yourself. Otherwise (否则), you might be the one with a note stuck on your back someday with no one to tell you."