Adding seven to five makes twelve and not thirteen.

Lazy Bones.

At first, there were 2 pears on the tree. After the wind blew, one pear fell on the ground. So there where no pears on the tree and there were no pears on the ground.

Pumps.

You can hang the iron rods on a string and watch which one turns to the north (or hang just one rod).
Another solution: take one rod and touch with its end the middle of the second rod. If they get closer, then you have a magnet in your hand

You can't blame me for something I didn't do.

There can live maximum of 518 people in the town. By the way, it is clear that one inhabitant must be baldy, otherwise there wouldn’t be a single man in the town.

Hip-Hop.

He rode on his horse named Friday.

High Five.

5832/17496 = 1/3

Once, because after you subtract it's not 25 anymore.