Learning Path

The learning path is developed through 4 sub-units that face the different aspects of constructing an energy-efficient scale model house.

Subunit 1: Testing an house model

This subunit guides students in the construction of a model house and in making explicit the different factors that contribute in heat dispersion and energy consumption to maintain warm the house. Each factor is analysed in the other sub-units that are also developed around a particular problem that guides the inquiry. It involves 3 student learning activities:

• Activity 1_1 aimed at the construction of different kinds of house models and at evaluating the main difficulties in maintain them warm;
• Activity 1_2 aimed at analysing the distribution of temperature inside the house model;
• Activity 1_3 aimed at analysing the heating effects of light on the house models.

Subunit 2: Conduction

This sub-unit analyses the role of different materials in heat dispersion by developing the relevant concepts connected with energy transfer through conduction. It has two activities:

Subunit 3: Convection

This subunit analyses energy transfer in fluid material and the main concepts connected with the convection process.

The starting point is the analysis of Activity 1_2 of sub_Unit_1 that will be supported by further observations performed in Activity 3_1 whose objective is to make evident the currents of hot fluids moving from hot to cold regions.

This activity will end by supplying an explicative model, i.e. a qualitative  mechanism of functioning explaining natural convection on the base of density differences among fluid volumes at different temperature. Such a model will be used in order to explain the “stack effect” or the “chimney effect”, where rising hot air pushes outward at the top of a building and cold air is drawn inward at the bottom.

A second activity (Activity 3_2) will analyse the effect of moving air on surface temperatures by confronting results of two experiments measuring natural cooling and forced cooling. Data can be analysed at different levels by characterising phenomena qualitatively or quantitatively in dependence of the classroom mathematical knowledge.

Subunit 4. Thermal Radiation

This subunit introduces the concept of energy transfer by radiation, analysing the different effects of solar radiation spectrum.

The starting point is the analysis of Activity 1_3 of sub_Unit_1 that pointed out that light can warm the walls of our house models and this warming effect is increased if the wall colour is dark or black.

The first problem to face is that to better measure the heating effects of radiation by constructing a simple “radiometer” (see Activity 4_1).

Activity 4_2 will measure the heating effect of sun radiation on bodies of different colours.

Activities 4_3  will show that our radiometers are able to make evident a radiation different than the visible one and introduce the IR radiation.

One of the last two activities can be chosen by the teacher according to the level of the classroom.

Activity 4_4 will propose an open inquiry approach to the analysis of IR apparatuses (video, images, thermometers,….)

Activity 4_5 proposes  a video were the same experiment is performed in presence and absence of atmospheric air in order to deepen the knowledge of IR radiation.

The following table characterises the activities from the point of view of the required type of inquiry and considering the 5E model of the Learning Cycle.