TEACHER : What is an island ?
Pupil   : A piece of land surrounded by water except on one side.
TEACHER :On one side ?
Pupil   : Yes, on top !
   
TEACHER :Give me three reasons why the world is round
Pupil   : Well my dad says so, my mum says so and you say so !

   
TEACHER : What shape is the world in?
Pupil   : Rotten !
   
TEACHER : Why does you geography exam have a big zero over it.
Pupil   : It's not a zero, the teacher ran out of stars, so she gave me a moon instead !
   
TEACHER :What's you name ?
Class   : Ravi

TEACHER  : You should say "Sir"
Pupil   : OK, Sir Ravi !