In this chapter, a board is set up with three surfaces. The students' hands compare the relative temperature of the surfaces on the board, and the board prompts students to investigate by asking them to determine which surface is coldest. After placing a hand on each for a few moments, a student usually finds the metal surface feels coldest. In reality, all the surfaces begin at room temperature—they feel cold, warm, and hot due to their different capacities to conduct heat away from the hand. This activity can appeal to a variety of ages, starting with students around 4th grade, and can fit into the classroom in a variety of ways.