Contextualization

The physical properties of materials are intrinsic characteristics that determine how they react to different situations and environments. It is these properties that allow us to have sturdy buildings, comfortable clothes, safe cars, fast computers, and many other products we use in our daily lives.

Piaget, in his theory of child cognitive development, describes that students in this age group are in the stage of concrete operations. In this stage, children begin to develop the ability to think logically about objects and events. Therefore, knowing and understanding the physical properties of materials is essential for them to interact safely and effectively with the world around them.

Still in this stage, concrete experiences, which involve manipulation and observation of materials, are the ones that most favor learning. Therefore, direct contact with different materials, their properties, and behaviors will offer students the opportunity to identify, understand, and consequently, better manipulate the environment around them.

All objects in our surroundings are made of some type of material, each with its specific physical properties. To better understand the relevance of these properties, let's consider some examples: metals, for instance, are used in pot handles due to their high thermal conductivity. Plastics, which have low thermal conductivity, are used to insulate electrical wires. Ceramic-based materials, which are hard and heat-resistant, are used in plates, bricks, and tiles.

In terms of resources for further exploration of the topic, I suggest the use of the book "Material World: A Global Family Portrait" by Peter Menzel, which explores how people around the world use materials in different cultures and contexts.

The website "Ciência em Casa" (Science at Home), maintained by the Science Museum of the University of Cambridge, offers a series of simple and safe experiments that can be carried out at home or at school to explore the physical properties of materials (https://www.scienceathome.uk/properties-of-materials).

Practical Activity "Discovering the Physical Properties of Materials"

Project Objective

The objective of this project is to allow students to discover in practice how some of the main physical properties of materials that surround us in our daily lives work.

Project Description

Students will carry out a series of simple practical experiments to explore and understand the physical properties of different materials. They will conduct these experiments in groups of 3 to 5 students and then discuss the results obtained and prepare a report to present their findings.

Required Materials

• Transparent glass or plastic containers
• Different materials for experiments, such as: wood, metal, plastic, rubber, paper, stone, cotton, etc.
• Ruler
• Scale to weigh the materials
• A magnet
• Heat source (can be the sun)
• Water
• Ice cubes

Step by Step

1. The student groups should gather and select four different materials to investigate.

2. One of the properties to be investigated will be density. For this, students should take a piece of each material, measure its dimensions with the ruler, and calculate its volume (they have learned how to calculate volume in previous classes). Then, they should weigh each piece of material on the scale and record its weight. Density is calculated by dividing the weight by the volume.

3. The second property to be investigated is thermal conductivity. For this, students should place a piece of each material in the sun and after some time, they can check which one heats up the most.

4. The third property to be investigated is the response to magnetic forces. Using a magnet, students should check which of the materials are attracted to the magnet.

5. The fourth property to be investigated is solubility. For this, students should place a piece of each material in a container with water and observe if any of them dissolve in water.

6. To conclude the project, each group should analyze the properties investigated and prepare a report on their findings.

Report

The report, to be written jointly by the group, should contain:

1. Introduction – In this section, students should briefly discuss the theme "Physical Properties of Materials", its relevance, applications, and the project's objective.

2. Development – Also in this section, it should include the theory about the investigated physical properties, a detailed description of the practical activities carried out, the procedures used, and the results obtained. The discussion of these results, comparing them with what was expected based on the theory, should also be included in this part.

3. Conclusion – Here, students will summarize the main points, talk about the learnings they had from the activity, and the conclusions they reached based on the experiment results.

4. Bibliography – Finally, students should list all the resources used to carry out the project, including books, websites, videos, and others.

The final report should be submitted one week after the experiments are conducted.