Students study and observe rocks and identify properties that can be used to classify or divide the rocks into groups. Students then identify other properties that could be used to classify or divide other objects into groups.

This task is designed to take students approximately 45 minutes to complete.

Overall Task Content Area:

Physical Science

Specific Knowledge Areas:

Properties of objects and materials

Properties of Earth materials

Performance Expectations:

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

4 A SI 1: Ability to do scientific inquiry: Grades K-4
1.3 Employ simple equipment and tools to gather data and extend the senses. In early years, students develop simple skills, such as how to observe, measure, cut, connect, switch, turn on and off, pour, hold, tie, and hook. Beginning with simple instruments, students can use rulers to measure the length, height, and depth of objects and materials; thermometers to measure temperature; watches to measure time; beam balances and spring scales to measure weight and force; magnifiers to observe objects and organisms; and microscopes to observe the finer details of plants, animals, rocks, and other materials. Children also develop skills in the use of computers and calculators for conducting investigations.

4 B PS 1: Properties of objects and materials: Grades K-4
1.1  Objects have many observable properties, including size, weight, shape, color, temperature, and the ability to react with other substances. Those properties can be measured using tools, such as rulers, balances, and thermometers.

1.2  Objects are made of one or more materials. Objects can be described by the properties of the materials from which they are made, and those properties can be used to separate or sort a group of objects or materials.

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.

(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 b. sort and classify objects according to their attributes and organize data about the objects
Grades pre K-5 d. design investigations to address a question and consider how data-collection methods affect the nature of the data set

GEO1: Analyze characteristics and properties of two- and three-dimensional shapes and develop mathematical arguments about geometric relationships:
Grades pre K-5 e. classify two- and three-dimensional shapes according to their properties and develop definitions of classes of shapes such as triangles and pyramids

MEAS2: Apply appropriate techniques, tools, and formulas to determine measurements:
Grades pre K-5 e. develop strategies for estimating the perimeters, areas, and volumes of irregular shapes.

PS3: Apply and adapt a variety of appropriate strategies to solve problems:
Grades pre K-5

RP3: Develop and evaluate mathematical arguments and proofs:
Grades pre K-5

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

REP1: Create and use representations to organize, record, and communicate mathematical ideas:
Grades pre K-5

General Instructions to the Teacher:

This task is designed to take students approximately 40-50 minutes to complete.

Students will be working in groups of 4 - 6 for the experiment/activity part of this exercise.

Students work together for up to 20 minutes. They are instructed to notify you when finished with the group work, and then to go on to the individual work beginning with question #1. If students are still working together 20 minutes after the testing begins, instruct them to cease their group work and begin individual work. At this point, they may no longer talk. Whether or not they are just beginning their individual work, remind students that they now have about 25 minutes to complete the individual activity.

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.

Materials for "Classifying Rocks":

At this station students should have:

• a set of 12 to 15 rocks, of various kinds, sizes, etc.
  
• hand lens
  
• pen or pencil

Advance Preparation:

None required.

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.

Extensions/modifications:

• Rubric language should be expanded and targeted to the specific NCTM standard(s) to be measured.

Advanced Preparation Set Up: