Grade 3 Science s1

Grade 3 Science

Unit Outline Title: Rock On! Topic Title: Rocks and Minerals Name of Lesson: How Hard is a Rock? Suggested Time: 1-2 class periods Standards: S3E1b, S3CS1, S3CS3, S2CS8 Essential Question(s): Unit: What are the physical attributes used to identify rocks and minerals? Lesson: How do you classify rocks and minerals by color? How do you classify rocks and minerals by shape? How do you classify rocks and minerals by texture? How do you know that one rock is harder than another? Assessment Description/Performance Task: Constructed response Informal assessment Performance task Selected response

Brief Description:  Children are going to observe and test objects for hardness using a streak test. Instructional Methods Hook  Conduct a quick survey of the class. Ask the following questions and tally the results on the board. You can choose to discuss the answers to each question as you go along, or allow the students to discover them as you complete the lab. 1. Are all rocks hard? (No some rocks are quite soft.) 2. Do you think you can scratch a rock using your fingernail? (Yes, you can.) 3. How many of you had rocks put into your diapers when you were little? (Power is made using talc.) 4. Do you think you would use rocks and minerals to brush your teeth? (Yes, calcium carbonate, limestone, sodium carbonate, and fluorine are all found in toothpaste.)

Experiment  Use the Harcourt Science Textbook Chapter 1, Lesson 1 p. C4-C5.  Create a chart in science journal to record observations. A sample one is provided for you on page C5.  Give each group of students sample minerals labeled A-G.  A harder mineral scratches a softer mineral. Try to scratch each of the other minerals with Sample A. Record which minerals Sample A scratches.  Visit http://library.thinkquest.org/J002289/index.html This site contains a “This Planet Really Rocks” Webquest. Students may review characteristics of rocks and minerals and much more.  Students can click on the http://library.thinkquest.org/J002289/mohs.html?tqskip1=1 This page contains a Moh’s hardness scale. Use the scale to explain the streak test method for determining hardness of objects.  Test the lead of a pencil with a fingernail.  Test a piece of chalk with a penny.  Test the pencil lead and penny with the chalk.  Test the chalk and penny with the pencil lead.  Test the chalk and pencil lead with the penny.  Record results after each test.

CCSD Version Date: July 14, 2006  List objects tested in order from hardest to softest.  Repeat test with rock and mineral samples to determine the hardest and softest rock and mineral.

Assessments  Summarize conclusions orally.  Ask students to write a 2 to 3 sentence response to one of the unit or lesson essential questions. Illustrations may be used to support their answers.  Collect student charts of rock and mineral hardness.  Use digital camera to capture the images of the rocks and minerals the students have put in order from softest to hardest. Differentiation:  Resource learners can be given a template to record information.  Target learners create a new way to test the hardness of rocks and minerals.  Target learners can also visit the Rock Sayings site located at this link: http://library.thinkquest.org/J002289/sayings.html Here students are asked to determine what these rock sayings mean and come up with one or two of their own. For this Lesson:  Rock and mineral samples  Penny  Chalk  Lead pencil  Data template  This Planet Really Rocks Webquest at http://library.thinkquest.org/J002289/index.html  Harcourt Science textbook Vocabulary:  (introduced in prior lessons)

CCSD Version Date: July 14, 2006