You know someone is not so bright if they are/have....

• Not the sharpest pencil in the pack.
  
• A few clowns short of a circus.
  
• Dumber than a box of hair.
  
• The wheel's spinning, but the hamster is dead.
  
• One taco short of a combination plate.
  
• A box of Cracker Jack with no prize.
  
• Body by Fisher, brains by Mattel.
  
• Couldn't pour water out of a boot with instructions on the heel.
  
• Fell out of the Stupid Tree and hit every branch on the way down.
  
• Are a few bricks short of a load.
  
• Has a few lose screws.
  
• Demonstrates proof that evolution can go in reverse.
  
• Has an IQ of 2, but it takes 3 to grunt.
  
• Is full of marbles.
  
• Counts to 10 using both hands and feet.
  
• Not playing with a full deck.
  
• Sharp as a butter knife.
  
• Thinks the test pattern is a new cable network situation comedy.
  
• Uses white-out* to make corrections on their computer screen.
  
• They trip over their cordless phone.
  
• They think the extra fork at dinner is in case they drop the other one.
  
• They jump out of a plane and ask for directions.
  
• They return their bag of M&Ms because it was full of W's.
  
• You catch them starring at an orange juice container because it reads concentrate.
  
• They ask lightbulbs for ideas.
  
• A couple of french fries short of a Happy Meal.
  
• Couldn't find his ass with both hands and a map.
  
• Took the Pepsi Challenge & chose Jif.
  
• Needs to look up the number to 911.
  
• Can't eat pickles 'cause their head won't fit in the jar.
  
• Tried snorting Coke & got the bottle stuck in their nose.
  
• Saw a sign that said "Disneyland left", so they turned around & went home.
  
• They are like a bottle of beer - empty from the neck up.
  
• You give them a penny for their thoughts, and get change!
  
• Thinks a box of Cheerios is "donut seeds".
  
• Thinks "nuclear fission" needs special bait.
  
• Thinks an innuendo is an Italian suppository.

Everyone is kneaded out of the same dough but not baked in the same oven. -- Yiddish proverb