A magnifying glass can start a fire even on an overcast day. A king size waterbed holds enough water to fill a 2000 sq foot house 4 inches deep. Legos will pass through the digestive tract of a four year old. Duplos will not. Play Dough and Microwave should never be used in the same sentence.
Super glue is forever.
McGyver can teach us many things we don't want to know. No matter how much Jell-O you put in a swimming pool you still can't walk on water. Garbage bags do not make good parachutes. Marbles in gas tanks make lots of noise when driving. You probably do not want to know what that odor is.