Lesson Description
This lesson focuses on sediments. The students will begin by learning how to "look" at sediments and classify them. They will also learn how about how sediment layers are examined and collected in cores. The activities provide students with opportunities to gain a better understanding of the core sampling process and how the layers of sediments are studied to reveal information about Earth's history.

SUGGESTED TIME FOR ENTIRE UNIT: 1 week (5 days)

Pre-Assessment
The pre-assessment is designed to assess students' knowledge regarding the stated lesson objectives.

Activities and Assignments
Materials
Layered Cake (To make: 2 pkgs White Cake Mixes, 1 pkg Chocolate Frosting, 1 Rectangular Foil Baking Pan, Food Coloring, Toothpick (or Tube Icing))
Straws (2 will be needed for each student or group to complete activities 1 and 2)
Colored Pencils enough so that students can illustrate their layers
Rulers one per group or student
Clay Layers (To make: clay or playdoh in several colors, large spices (not powdery- for example: parsley, course pepper, whole cloves), a thick tray or container for the layers (a butter container will work well))
Single Edged Razor (or exact-o knife or small sharp scissors) one per group or student
Journal Pages one per student for each exercise
Exercise 1 Journal
Exercise 2 Journal
Exercise 3 Journal

Optional:
Knife, Forks, Napkins will be needed if students will be permitted to eat the cake from Exercise 1
Beans, Rice, Noodles will be needed if the Teacher chooses to model the introduction in her classroom and have students compare the "mock" sediments as an intro to the unit
Handouts of the instructions may be created before the lesson to help students through the unit.
Exercise 1: Instructions, Preparation
Exercise 2: Instructions, Preparation

Procedures
As an option, the teacher may guide the students through the information by projecting the web lesson onto a screen. This is effective in classrooms where there may be fewer computers. Another option is to have students work on the unit themselves or in small groups, with the teacher monitoring as they navigate through the information on the website.

1. Through the Introduction, students will be introduced to sediments. They will be asked to compare and describe a pair of "mock" sediments. (The Teacher may choose to model the introduction pictures in the classroom to make them real. Students can compare and contrast the mock sediments as an intro activity to the unit.)

2. The Presentation begins by specifically defining how scientists classify sediments. Clastic and Organic sediments are shown and defined. Students are asked to compare the types of sediments. The presentation then goes into the source for sediments and into how they are layered and built up over time, representing Earth changes and geologic activity. The presentation ends with a discussion of sediment layer stratification and sequencing.

3. The Activity involves 3 exercises. Each of the exercises has an accompanying journal page for students to fill out. The first two exercises are hands-on modeling exercises to learn about how sediment core samples are collected. They model the way in which scientists collect and study sediment core samples. The final exercise takes the students through the process of collecting a real core sample on the web. The teacher should print out the journal pages (see links above) for students to fill out as they complete each of the activities.

-EXERCISE 1
This exercise involves examining the layers of a cake. Students will use straws to obtain "core samples" of a cake to get an idea of the different layers of the cake. The cake models the sea floor. The straw simulates the drill that obtains the sediment core samples. The layers and different colors in the cake simulate the sediments layers that are revealed through the coring process. Students will examine their core samples through completing the journal page that uses the scientific processes, making hypotheses and conclusions. Since the journal results will depend on what the student sees and interprets, an answer sheet is NOT given. Assessment of the journal page will be left to the discretion of the teacher.

-EXERCISE 2
This exercise is similar to Exercise 1. In this activity, students will obtain a core sample from layers of clay that have been prepared by the teacher. They will again use a straw to obtain a "core sample" of the layers, to get a bigger picture of what lies beneath the clay formation's surface. Once again, a journal assignment asks students to apply the scientific process to their examination of the "sediment core" models. Just as above, assessment of the journal page will be left up to the teacher.

NOTE: This activity DOES involve using a razor or sharp scissors! Students who are not able to work safely should NOT be allowed to use these materials! The teacher may have to provide assistance or modify the assignment (by keeping the samples in their straws) to prevent injury.

-EXERCISE 3
This activity is entirely web-based. Students will follow along as the procedure for obtaining a core sample is described. Students can click on each picture of this section for more information. They will be asked questions through the journal page that will require them to think about what they have learned concerning the process of drilling (coring), collecting a sample, studying the sediments, and storing the core samples. There is no answer key for the journal page because of the open-ended nature of the questions. The teacher should look for answers that represent knowledge of the coring processes and of the information from the webpages in this exercise.

To conclude the unit activities, the teacher should hold a wrap-up discussion about sediments, layers, sediment cores, and sediments are studied to learn about the Earth's history. Students may explore the related links for more information.

Tools and Resources
Hardware used in this lesson:
Computer: With keyboard, mouse, and operating system such as Windows 95
Printer- (optional): For printing out instructions and assessments for the class
Projector- (optional): Such as a Proxima projector, that is capable of projecting computer images onto a screen so that the whole class may view the lesson along with the teacher
Software used in this lesson:
Microsoft Internet Explorer or Netscape Navigator: To view the lesson, access the links, data, and pictures
Microsoft WORD: To view printable documents and print them.
Web sites used in the lesson:
Sedimentary Rocks: This site shows different types of sedimentary rocks. Students can look at the different textures and features of sedimentary rocks.
Sedimentary Deposits: Students can view pictures of a wide variety of sedimentary deposits and their internal structures on this website.
The Drill Ship-JOIDES Resolution: This site describes the drill ship used to collect sediment core samples.

Extensions and Modifications (Optional)
As a modification for Exercise 1, the teacher may use cupcakes instead of layer cake for each student. By using the cream filled, layered Hostess-type cupcakes, the students may conduct core samples on their cupcake, recording where they stick in the straw to get the samples as they go along.

An extension activity may involve a class paper recycling bin. If your class has a paper recycling bin, your students can model how scientists study the past by excavating the layers of paper to model the layers of rock. First, divide students up into groups. Have each student excavate a certain amount of paper from the bin (in centimeters). Each group should get a different layer of the bin and learn as much as they can about their layer. Have students record their data similar to the way they recorded information in their journals for exercises 1 and 2 (these journals may be modified so that they are appropriate). Students may examine the subjects of the paper, the size or type of paper, the dates on the paper, etc. to get an idea of what their sample of paper tells about all the paper in the recycling bin and what it tells about the history of activities in the classroom.

This lesson may be modified in its presentation. The teacher may want to do the lesson from the computer, projecting the information on a screen in front of the class and asking questions along the way. Presenting the lesson in this way may assist students who are not comfortable with navigating around the Internet or in classrooms where there are few computers or Internet connections.