## Graph Both Crusts

### Lois WalshBay District Schools

#### Description

Students calculate the angles and construct a pie graph of the percentages of the elements in the continental and oceanic crusts. Then they analyze the results.

#### Objectives

Uses concrete and graphic models to derive formulas for finding rate, distance, time, angle measures and arc lengths.

Interprets data that has been collected, organized, and displayed in charts, tables, plots.

#### Materials

-Earth Science textbook, encyclopedia, or other reference chart that has the elements present in the earth’s crust.
- Calculators
- Conversion Table Worksheet
- Protractors

#### Preparations

1- Review procedure.
2- Create an overhead or board visual for:
a- math review of formula and measurement.
3- Set out materials and worksheets.

#### Procedures

1. Students need the percent of the elements in the earth’s continental crust and the oceanic crust. This can be given to them on page numbers or tables in the textbook or they can be assigned the task of researching the percentages.

2. Review the math involved in the activity.
A) Students need to know that the number of degrees in a circle is _______(360). 1% of 360 is _______(3.6) (It is a division problem.)
B) Students need to know how to measure, mark, and draw an angle with a protractor.

3. Pair students into groups of two and assign each a task.
A) Convert percent of an element to an angle for the pie graph. Record on conversion table.
B) Measure the angles, then label and construct a pie graph showing the % of elements in the crust.

4. Do the first one as a sample together.

5. Let students perform the task. Have students check their partners' work for correctness, and answer the analysis question about the graphs. Monitor students' progress.

6. Review the tables, graphs, and answers as a class.

7. Post the tables and graphs after assessing.

#### Assessments

The Conversion Table Worksheet, questions, and the graph should be used to assess the student's understanding. (See associated file) Acceptable understanding of the benchmark part that deals with angles would be demonstrated by at least 80% accuracy of the worksheet, questions, and graph construction. Students should also correct any incorrect answers for the most complete understanding. If the accuracy is less than 80%, have partners switch tasks and complete the activity.(Students can even change partners the second time.)
Note:
This can be a formative or a summative assessment depending on the students' experience in constructing pie graphs and tables.

#### Extensions

-Use the same procedure on percentage of elements in minerals.
-Student could do both tasks themselves.

#### Attached Files

The file is the Conversion Table Worksheet and questions for the activity.     File Extension: pdf