Here are some really lame French/English puns:
Once upon a time in winter three french cats, called Un, Deux and Trois, went skating on a pond. The ice gave way and Un, Deux, Trois cats sank.
Why does Mitterrand only have one egg for breakfast?
Because un oeuf est un oeuf.
There was a class having a lesson, and one boy said:
"Miss, can we do French now?"
The teacher replied, "Mais oui."
The boy said, "Sorry, may we do French now?"