Heat the end of the strip of aluminum. You will notice that the wax drops melted more quickly than on the nail. Pinch the edge of the square with a clothespin and hold it over the flame. The wax at all corners of the triangle also melted at nearly the same time. Aluminum is an excellent conductor.
Metals are good conductors.
Other materials that heat cannot move through easily are called insulators. Divide students into 4 groups. Give each group an identical jar of hot tap water. Screw on lid tightly. Have each groups choose from a variety of materials to wrap and insulate their jar.