Review your lesson plans for patterns. Look for gaps in time that may routinely give the student time to act inappropriately. Identify activities or times during the day when the student may be more disruptive.
Brainstorm what the student's behavior may reveal about his emotional needs. The student may feel ignored, isolated, hurt, misunderstood, or socially awkward. Avoid mislabeling a student as a problem child when there could be a real cause for his actions.
Plan a specific time for the student, or any student, to release extra energy or incorporate movement into your lesson plans. This will give the student the attention he craves without disrupting the classroom environment.
Announce to the students your expectations of their behavior and maturity. Specify that funny behavior is best left for certain, designated times and not whenever a student may like.
Talk one on one with the student. Address his positive behaviors in addition to his less desirable behaviors; this may also be a good time to talk about respect. Reiterate that humor is good at an appropriate time and place.
Create an awards and consequences system based on behavior guidelines that you previously set for the class. If necessary, include an extra award or privilege for the student.
Counteract clownish behavior using body language. Establish eye contact with the student, stand near him, or discuss a secret cue that only the two of you will know.