[pompeylass]

A little 5 year-old lad has a week off from school - teacher wants to know why he was away.
He says 'My mum was in bed, cos she had a bus'.

The annoyed teacher doesn't except this lame excuse. 'Well, perhaps it was a coach she had, then', says the boy.
Teacher says 'Tomorrow, I want a note from your parents telling me the reason, or else'.

Next day the boy gives a note to the teacher, who reads it. 'Ah! It seems your mother's had a mis-carriage, lad. I'm sorry to hear that'

'Ahh! That's it. I knew it was something on wheels'.