Description:

This event assesses the students' abilities to formulate and apply rules that they can use to compare and rank things. The specific subject is the hardness and softness of minerals. It asks them to perform a scratch test on four unknown mineral samples, read a bar graph that illustrates the comparative hardness and softness of four named minerals, then combine the scratch test results with the bar graphâs information to identify the four mineral samples.

The students must already know: (1) fingernails are softer than pennies and pennies are softer than nails; 2) harder things scratch softer things; 3) how to read a bar graph.

Students will be working in groups of 4-6 for the experiment/activity part of this exercise. Each student must record the information in his or her own booklet (test papers). Allow from 20 to 25 minutes to complete the group work, and a similar time period for students to do their individual answers to the test questions.

Overall Task Content Area:

Earth Science

Properties of Earth materials

Performance Expectations:

• conducting investigations
• using equipment
• gathering, organizing, and representing data
• formulating conclusions from investigational data
• applying scientific principles to develop explanations and solve new problems

4 D ESS 1: Properties of Earth materials: Grades K-4
1.1 Earth materials are solid rocks and soils, water, and the gases of the atmosphere. The varied materials have different physical and chemical properties, which make them useful in different ways, for example, as building materials, as sources of fuel, or for growing the plants we use as food. Earth materials provide many of the resources that humans use.

4 A SI 1: Ability to do scientific inquiry: Grades K-4
1.4 Use data to construct a reasonable explanation. This aspect of the standard emphasizes the students’ thinking as they use data to formulate explanations. Even at the earliest grade levels, students should learn what constitutes evidence and judge the merits or strength of the data and information that will be used to make explanations. After students propose an explanation, they will appeal to the knowledge and evidence they obtained to support their explanations. Students should check their explanations against scientific knowledge, experiences, and observations of others.


(Use the "hot" link on the PALS home page to check the full text of related National Science Education Standards, if desired.)

National Council of Teachers of Mathematics:

DAP1: Formulate questions that can be addressed with data and collect, organize, and display relevant data to answer them:
Grades pre K-5 e. collect data using observations, surveys, and experiments
Grades pre K-5 f. represent data using tables and graphs such as line plots, bar graphs, and line graphs

DAP3: Develop and evaluate inferences and predictions that are based on data:
Grades pre K-5 b. propose and justify conclusions and predictions that are based on data and design studies to further investigate the conclusions or predictions

PS2: Solve problems that arise in mathematics and in other contexts:
Grades pre K-5

CON1: Recognize and use connections among mathematical ideas:
Grades pre K-5

REP2: Select, apply, and translate among mathematical representations to solve problems:
Grades pre K-5

Materials for "Minerals":

At this station students should have:

• 1 penny
• 1 nail
• 1 piece of quartz (labeled "A")
• 1 piece of calcite (labeled "B")
• 1 piece of talc (labeled "C")
• 1 piece of hornblende (labeled "D")
• 1 pen or pencil

Advance Preparation:

No special advanced set-up is needed for this exercise. Each group should be given a set of materials to work with.

Students should be ready to work as soon as the period begins. Group assignments should be made in advance. The materials should be set out at each lab station, if possible. A central supply area, if needed, should be easily accessible. All supplies should be clearly labeled.

Safety:

• Be careful.
• Teachers and students should always exercise appropriate safety precautions and utilize appropriate laboratory safety procedures and equipment when working on science performance tasks.
  

Advanced Preparation Set Up: