Topic: Not all rocks are hard

Author: Zyta Sendecka

Target group

Students of the 4th grade of an elementary school.

Core curriculum

4th grade

VI. The natural environment of the nearest area. The student:

4) identifies rocks that occur near the area of residence.

The general aims of education

The students name, identify and define the properties of some rocks.

Criteria of success

• name three types of rocks;

• give one example for the selected type of rock;

• determine the hardness of a rock;

• identify rocks containing limestone.

Key competences

• communication in the mother tongue; 

• communication in foreign languages;

• mathematical competence and basic competences in science and technology; 

• digital competence; 

• learning to learn; 

Methods / techniques

Conversation, work with text and work with the use of the model, laboratory work.

Individual work and work in pairs.

Teaching aids

• abstract;

• interactive or traditional board;

• tablets/computers;

• collection of rocks.

Lesson plan overview (Process)

Before lesson

Before the lesson, for example during a trip, the students collect various rocks (stones) that they bring to the lesson.

Introduction

1. The teacher asks the students a key question: What is someone like who is hard as a rock?

2. The teacher gives the topic, the goal of the lesson in a language understandable for the student, and the criteria of success.

Realization

3. The teacher uses the graphic entitled „Types of rocks” to familiarize the students with the types of rocks.

4. The teacher displays a film: „How rocks are formed?” and asks the students to observe the difference in the formation of different types of rocks.

5. The teacher hands out sets of rocks to a pair of students: granite, limestone and marble. The teacher asks the students to look at the collected stones using the magnifying glass and divide them into three types: magmatic, sedimentary and metamorphic. As an additional help for the exercise, the teacher recommends an interactive graphic from the abstract.

6. The teacher displays the correct match.

7. Then, the students perform the interactive task indicated by the teacher themselves.

8. The teacher gives the students black and white pieces of paper. The teacher asks the students to use their own rock collections to divide them into two sets due to their hardness to those that draw on a piece of paper (white or black), and those that do not leave a trace. Then, the teacher gives each student a nail and asks for an attempt to scratch the rocks. The students divide the rocks into those that can be scratched using a fingernail (a line or a trace of dust), and those that cannot be scratched with a fingernail, but a silver nail trail remains.

9. The teacher gives two beakers, vinegar and two named rocks, granite and limestone, to each pair of students. The students put samples of rocks into the beakers and pour vinegar so that the liquid covers them, and observe the effect. The teacher asks the students to formulate observations. The teacher explains the observed effect to the students. Then, the students check their collection of rocks using the vinegar and divide them into those containing limestone, and other ones.

Summary

The teacher asks the students to do the selected interactive exercises by themselves.

Homework

The teacher asks the students to do one of the tasks:

1) Search for information and note how rocks are used in everyday life.

2) Let us create our own mineral cosmetic. Put 2 tablespoons of sea salt or thoroughly cleaned (roasted) minor sand in a plastic cup, add 3‑4 tablespoons of olive oil or honey and mix it. Use it as peeling and describe the condition of the skin after the procedure.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

Not all rocks are hard

When we say that he/she is hard as a rock, we mean that they are strong, unyielding and unbreakable. In reality, besides the proverbial hard rocks there are also other types of rocks: soft, and even loose. Rocks include not only hard marble, but also soft clay and loose sand.

When you look around you may see some stones – they are nothing else but pieces of rocks. Rocks are groupings of one or several minerals, i.e. substances with certain properties and specific composition. Some rocks are formed as a result of cooling down of hot, liquid substance from the depths of the Earth. These are magmatic rocks. Sedimentary rocks are created by deposition of particles of other rocks and remains of living organisms. Metamorphic rocks are formed from existing rocks that change their properties as a result of various processes inside the Earth (e.g. high temperature and pressure).

Rocks may be also subdivided by how closely mineral particles cling together. If mineral particles are loose (like in the case of sand or gravel) we speak of unconsolidated rocks. Solid rocks are those that may be crushed only by some tools. Mineral particles are strongly cemented, i.e. bound together. In everyday lives, we often encounter artificial man‑made materials; since they are not natural mineral groupings, they may not be called rocks. Such materials include concrete, bricks or school chalk.

In different parts of our country we encounter different rocks on the surface of the Earth. Unconsolidated rocks predominate in the north and central Poland. Sand and clay are the most common types of rocks in those parts. Limestone is common in the uplands. Limestone is easily damaged by water and wind. That is why the landscape in places with a lot of limestone is very diverse; in such places you may encounter, for example, mushroom rocks and caves. In the uplands you may also encounter slate and sandstone. Mountains consist of resilient, hard rocks like granite, marble, gneiss and basalt.

• Minerals are the basic components of rocks.

• Rocks are a natural concentration of minerals.

• Due to the method of formation, rocks are divided into magmatic (e.g. granite), sedimentary (e.g. limestone) and transformed (e.g. marble).

• The most common types of rocks in Poland are sand, clay, limestone, sandstones, slates, and granite.