Why didn't the T-rex skeleton attack the museum visitors? Because she had no guts!
Why are there old dinosaur bones in the museum? Because they can't afford new ones!
The Burglar and the Sad Guard
A burglar was sneaking into a museum, and he had to get past the guard on duty.
As he snuck behind the guard, he couldn't help but notice the guard had his head in his hands, and he was crying. "I can't believe I've worked here for 10 years, and everyone has forgotten my birthday again!" He moaned. "Longer hours, more work, and no appreciation! I can't do this anymore!" The guard said to himself as he continued to sob.
The burglar could easily sneak past, but found himself feeling bad for the guard. Instead of proceeding with his plan, the burglar's sympathy for the guard got the better of him. He marched right down to the museum curator's office and kicked in the door.
There sat the director of the museum, the head of HR, and the head of security in a meeting.
"What are you doing here? How did you get pass the guard?!?" shouted the museum director.
"Gentlemen," said the burglar, "I'm afraid you've let your guard down."