Teacher: Why is your paper blank? Student: Sometimes silence is the best answer ! :D :D
Fax.
One of them has papers.
One says, "Spit out your gum!" The other goes, "Choo Choo Choo"
Angles in the Outfield
A student used to give his teacher some raisins everyday. He kept giving them for 3 months straight. Then one day he did not give raisins to his teacher. And his teacher asked him "Where are the raisins today?", and the boy said "My rabbit died."
None, that's what students are for.
You can silence a gun.
Mine's "silence".