What do I want students to learn? that objects expand when its temperature increases and contract when it falls. That this happens both in solids, liquids and gases. That students appreciate some of the practical consequences of these phenomena in daily life. COMMENT The purpose of this step is to establish learning goals clear and achievable. For that we must take into account the time available (a class), the stage of cognitive development of students (primary level) and the central ideas we want to bring the issue forward.
One possible way to achieve this goal list is to take note of all that we are going to occur and then discarding and staying with the more central that fit into the time available. Below are examples of other potential targets that we have discarded. 1. Define, understand and measure the coefficient of expansion of different materials 2. To understand that the coefficient of expansion is different for different solids and fluids, but that all gases have the same coefficient of expansion. 3.
Quantitatively express the law of Charles and Gay-Lussac 4. Appreciate that the gas density decreases when heated. 5. Let them know that ice is less dense than liquid water.