Recognize a student's creativity or sense of humor when it is appropriate. Laugh yourself, let the class laugh too, and then they should know that it's back to business.
Be a bit funny yourself, even if it is a little out of your comfort zone. I often refer to something funny that happened in class, or on a field trip. Everyone in the class experienced it, and thus, it is funny to everyone.
One hot lunch day, everyone got jello except for my 8th grade homeroom students. We laughed about that all year, and often brought in jello for the whole class.
Don't be too cool to not dress up on a designated February Fun Day.
Never, ever laugh at a student unless he is laughing at himself first, or unless you've checked with him ahead of time and gotten approval to tell a funny story about him.
Always be able to laugh at yourself. If you can do that, it can diffuse just about any situation, get you out of awkward moments or blunders, and a multitude of other traumas.
The very first year I was in the classroom, probably the first month I was teaching, in the first class of the morning, I noticed that every time I turned around to write on the board, the students began giggling. And it got a little louder every time I turned around. I made a casual comment about sitting in gum or something, but they gave me no clues. This went on for awhile. I think I said something like, "Just tell me! Whatever it is can't be that big of a deal." I made sure my slip wasn't showing. Silence. More giggles every time I turned around. I just ignored it and kept going.
Finally, one girl in the front row motioned for me to come over to her. When I got there, she whispered, "The lining on your dress collar is sticking out in the back."
I made some comment like, "Is that all it was? That's no big deal. Watch. I can stick it back in." Then I laughed and went on with my lesson. It is so much better to laugh at yourself than to get embarrassed and cry or something awful like that.
This reminds me of another story. When I was in the fourth grade, we had a young man who was student teaching. He always wore black pants, and every day he would lean against the blackboard and get a big white chalk line across the back of his pants. No one ever told him, but many of the students giggled at him.
One day, I decided to tell him. I can't believe that he hadn't figured it out by then, but he hadn't. He thanked me, and I don't think he ever leaned on the chalkboard or had a line on the back of his pants again.
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