Goal.

This lesson is intended to teach the students the different types of rocks by observing rocks samples and by searching in the Internet the rocks, minerals and gems sites. The students will also learn how important rocks minerals and gems are in our daily life.

Overview.

Rocks are made of minerals whose properties very often make them so pretty that people in culture all over the world use them as ornaments. Rocks are also used very practically. They are used in a variety of ways in construction of roads and buildings. Metal such as iron aluminum extracted from rocks are essential components in manufacturing cars and machinery, pans and medicines. For these reasons, it is useful to get the students interested in the learning of the various types of rocks in order to establish the foundation for more elaborate studies in high school and college.

Materials.

The materials will comprise, computers with internet access, several samples of igneous rocks, sedimentary rocks, metamorphic rocks, sand, mud, pebbles, goggles for each student, hammer, collection bag, markers.

Safety precautions.

Remind students to handle rock samples carefully. No throwing rocks! wear goggles.

Invitation.

The teacher will ask the students to bring any kinds of rocks samples they may encounter in their surroundings. The instructor will also provide additional and various rock samples available in the school. He or she will encourage the students to brainstorm about the samples and record on a sheet of paper their observations.

Exploration.

Planning and implementing tasks is an important role of a constructivist teacher. Consequently, the teacher in this lesson will divide the class into cooperative learning groups of three or four students. Provide each group with sand, rock samples. Ask the students to categorize the rock samples according to their own criteria, and record their observations in their small group discussions. The instructor will also show the students how to use the internet to search for relevant information. The students will practice by searching and "harvesting material from web sites such as:

Smithonian Gem & Mineral collection

http://galaxy.einet.net/images/gems/gems-icons.html

DMS Mining, Mineral and Much More

http://www.travel-net.com/~Index.html

Colorful atlas of the USA

http://fermi.jhuapl.edu/states/states.html

Explanation.

Having surfed the Internet and gathered the necessary in formation on the rock types, the instructor asks every small group to present to the entire class their different rock categories based on their internet hunt and an the samples at hand. The task of the teacher at this stage of lesson will be to correct the students misconceptions about the genesis of the three rock types. Here is also the time for the students to discover new concepts related to this lesson. With the guidance of the teacher, each group will refine their classification according to the texture of the rock samples. He or she should help the students make connections between the three rock types by drawing the rock cycle.

Take action.

The idea of rock classification into igneous, sedimentary and metamorphic rocks may be expanded by rock collection field trip, a scavenger hunt in downtown Atlanta to discover the use of rocks in construction and in jewelry.

Assessment.

The teacher may ask the students to draw a concept map connecting the concepts learned in this unit.