A biology teacher wanted to teach his class a lesson about the evils of alcohol, so he produced an experiment that involved a glass of water, a glass of whiskey, and two worms. “Now, class, observe closely the worms,” said the professor putting a worm first into the water. The worm in the water writhed about, happy as a worm in water could be. The second worm, he put into the whiskey. It writhed painfully, and quickly sank to the bottom, dead as a doornail. “Now, what lesson can we derive from this experiment?” the teacher asked. One bright boy raised his hand and wisely, responded, “Drink whisky and you won’t get worms.”
Teachers… have fun!
Announce that you need to deliver two lectures that day, and deliver them in rapid-fire auctioneer style.
Pick out random students, ask them questions, and time their responses with a stop watch. Record their times in your grade book while muttering “tsk, tsk”.
Gradually speak softer and softer and then suddenly point to a student and scream “YOU! WHAT DID I JUST SAY?” 
Announce to students that their entire grades will be based on a single-question oral final exam. Imply that this could happen at any moment.
If someone asks a question, walk silently over to their seat, hand them your piece of chalk, and ask, “Would YOU like to give the lecture?”
Every so often, freeze in mid sentence and stare off into space for several minutes. After a long, awkward silence, resume your sentence and proceed normally.
Wear mirrored sunglasses and speak only in Turkish. Ignore all questions.
Pass out dental floss to students and devote the lecture to oral hygiene.
Announce that the entire 32-volume Encyclopaedia Britannica will be required reading for your class. Assign a report on Volume 1, Aardvark through Armenia, for next class.
Announce “you’ll need this”, and write the suicide prevention hotline number on the board.
Turn off the lights, play a tape of crickets chirping, and begin singing spirituals.
Ask students to list their favourite shows on a signup sheet. Criticise their choices and make notes in your grade book.
Sprint from the room in a panic if you hear sirens outside.
Refer frequently to students who died while taking your class.
Show up to lecture in a ventilated clean suit. Advise students to keep their distance for their own safety and mutter something about “that bug I picked up in the field”.
Announce that other sections have almost finished their class projects.
Tell your math students that they must do all their work in a base 11 number system. Use a complicated symbol you’ve named after yourself in place of the number 10 and threaten to fail students who don’t use it.
Address students as ‘worms’.
Stop in mid-lecture, frown for a moment, and then ask the class whether your look fat.
Give an opening monologue. Take two minute breaks every ten minutes.
Of course, the most fun thing to do on the first day of class is to enjoy yourself, sleep in, and let the students wonder if they found the right room!
