Look around, see what you saw. Take the saw, cut the table in half. Put two halves together to make a whole. Put the hole on the wall and escape.
Turn on one switch and leave it on for ten minutes. This will make one of the bulbs hot. Turn off that switch and turn on another one. Immediately go upstairs. The cold bulb that is turned off is controlled by the switch you did not flip at all. The hot bulb that is turned off is controlled by the switch you turned on and then back off. Lastly, the bulb that is on is controlled by the switch you flipped last.
Teeth.
Man – crawls on four legs as a baby, walks on two legs as an adult, and walks with a cane in old age.
Fish.
A mountain.
A map!
Light two ends of one rope on fire and light one end of the second rope on fire. Then, when the first rope burns away completely, you know that a half hour has passed. Exactly when this happens, light the second end of the second rope on fire. From the time that you light the second end of the second rope to the time that it burns away is exactly fifteen minutes.