Read your book. Upside down.
Every time the person next to you turns the page, make a strange sound, or a beep.
Act like you’re picking your nose. And eating it.
Read out loud attempting to pronounce easy words. Butcher them badly. But be able to pronounce hard words.
Bring a recording of a popular song. Play it on headphones quietly, but sing along very badly. Then say to the person next to you, "I took singing lessons!"
Instead of a laptop, bring your entire computer!
Suddenly grasp your heart, let out a wail, and fall to the ground. Then get back up like nothing happened.
Start arguing with yourself. When they ask you who you are talking to, say, "Your just jealous ‘cause the voices are talking to ME!!!"
Bring a bottle of glue and sniff it while counting down from a very high number. When they ask what you’re doing, say, "I’m counting my brain cells!"
Maintain a look of horror constantly, but act normal other wise.
Get a child’s book like "Green Eggs and Ham" and complain that there is no glossary.
Find a thesaurus and say in complete astonishment, "Wow! Did you know that ‘affirmative’ and ‘yes’ mean the same thing?"