ALEX Lesson Plan


Fascinating Fossils

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  This lesson provided by:  
Author:Kathy Perkins
System: Tuscaloosa City
School: Tuscaloosa City Board Of Education
  General Lesson Information  
Lesson Plan ID: 35605


Fascinating Fossils


Students will explore how changes in rocks and land formations over time explain the large number of aquatic fossils that can be found across the state of Alabama. They will model volcanic eruptions and fossil formation through a hands-on activity using baking soda, vinegar, and playdough.  Then they will read a news article to determine that Alabama was underwater at one time, which explains how aquatic fossils are found across the state.  Finally, they will write and illustrate an explanation that shows how layers and fossils found in rock are evidence that these rocks changed over time.

This lesson results from the ALEX Resource Gap Project.

 Associated Standards and Objectives 
Content Standard(s):
English Language Arts
ELA2015 (2015)
Grade: 4
23 ) Write informative or explanatory texts to examine a topic and convey ideas and information clearly. [W.4.2]

a. Introduce a topic clearly and group related information in paragraphs and sections; include formatting (e.g., headings), illustrations, and multimedia when useful to aiding comprehension. [W.4.2a]

b. Develop the topic with facts, definitions, concrete details, quotations, or other information and examples related to the topic. [W.4.2b]

c. Link ideas within categories of information using words and phrases (e.g., another, for example, also, because). [W.4.2c]

d. Use precise language and domain-specific vocabulary to inform about or explain the topic. [W.4.2d]

e. Provide a concluding statement or section related to the information or explanation presented. [W.4.2e]

SC2015 (2015)
Grade: 4
12 ) Construct explanations by citing evidence found in patterns of rock formations and fossils in rock layers that Earth changes over time through both slow and rapid processes (e.g., rock layers containing shell fossils appearing above rock layers containing plant fossils and no shells indicating a change from land to water over time, a canyon with different rock layers in the walls and a river in the bottom indicating that over time a river cut through the rock).

Insight Unpacked Content
Scientific and Engineering Practices:
Constructing Explanations and Designing Solutions
Crosscutting Concepts: Patterns
Disciplinary Core Idea: Earth's Systems
Evidence of Student Attainment:
  • Construct explanations by citing evidence found in patterns of rock formations that Earth changes over time through both slow and rapid processes.
  • Construct explanations by citing evidence of fossils in rock layers that Earth changes over time through both slow and rapid processes.
  • Cite evidence from patterns in fossils in rock layers to support an explanation for changes in a landscape over time.
Teacher Vocabulary:
  • Evidence
  • Patterns
  • Rock Formations
  • Fossils
  • Rock Layers
  • Landscape
  • Marine fossils
Students know:
  • Different rock layers found in areas can show either marine fossils or land fossils.
  • Ordering of rock layers (e.g. layer with marine fossils found below layer with land fossils).
  • Presence of particular fossils (e.g., shells, land plants) in specific rock layers as evidence of Earth's changes over time.
  • The occurrence of events (e.g., earthquakes) due to Earth forces.
Students are able to:
  • Observe evidence from rock patterns in rock formations and fossils in rock layers to support an explanation for changes in a landscape over time.
  • Identify evidence from rock patterns in rock formations and fossils in rock layers to support an explanation for changes in a landscape over time.
  • Articulate and describe from evidence patterns in rock formations and fossils in rock layers to support an explanation for changes in a landscape over time.
  • Use reasoning to connect the evidence to support the explanation including the identification of a specific pattern of rock layers and fossils.
Students understand that:
  • Local, regional, and global patterns of rock formations reveal changes over time due to earth forces, such as earthquakes. The presence and location of certain fossil types indicate the order in which rock layers were formed.
AMSTI Resources:
AMSTI Module:
Water and Landforms

Local/National Standards:


Primary Learning Objective(s):

Students will construct a graph to track how their thinking changes over the course of the lesson. 

Students will model the formation of landforms. 

Students will write an explanatory text using evidence found in rock layers and fossils to explain how Earth changes over time. 

Additional Learning Objective(s):

 Preparation Information 

Total Duration:

61 to 90 Minutes

Materials and Resources:

Alabama shark tooth fossil (If fossils are not available, view the McWane Center fossil database.)

Playdough in 4 different colors

  • If purchased, use one can of each color for every 2 groups of students.
  • You may make your own with water, flour, salt, food coloring, oil, and cream of tartar using this recipe.  One recipe of each color will be enough for 4 - 5 groups of students.

Small Paper Cups (bathroom-size, one cup per student)

Vinegar (1 bottle)

Baking soda (1 box)

Straws (one per student)

Plastic knives (1 per group of 4 students)


Paper and pencils

Paper towels or napkins

Gadsden Times Article, “Miles from Ocean, Creek Contains Reminders of Prehistoric Sharks” (can be printed for each student or displayed for whole-class guided reading)

Evaluation Checklist for each student

Blue sticky note for each student

Yellow sticky note for each student

Chart paper

Toothpicks (1 per group of 4 students)

Optional materials for building student background knowledge about fossils and rocks:

Technology Resources Needed:

Teacher computer with interactive whiteboard or projector for showing websites

Optional (for acceleration) - student computers or tablets for interactive websites 


Background Information: Alabama is one of the most biodiverse states in the country. The state has many different ecosystems due to the large number of freshwater lakes, streams, and rivers as well as land features that vary from forests in the mountains to the estuary in Mobile Bay.  Alabama also has a rich fossil record that shows how much Alabama’s geologic features have changed over millions of years.  Many fossilized shark teeth have been found in central Alabama, showing that the state was once under the ocean.  Road cuts and canyons formed by running water show the layers formed in rock over time.  These layers show how rock formations change through erosion and sedimentary deposits, and the fossils encased in rock show Alabama’s unique history.  While a field trip is not required to complete this lesson, there are many sites in Alabama that give students the opportunity to see rock layers and fossils firsthand.  Consider taking a class field trip to one of these state parks, national parks, or museums to enhance your students’ understanding of fossils and rock formations.

To learn more about fossils and how they are formed, visit or

Since this is an introductory lesson, students do not need specialized skills to complete the lesson, but they should be familiar with the term fossil.  If students do not have prior experience with fossils, build background knowledge with the books listed in the materials section.

Preparation: Make or buy playdough and separate it into pieces for each group.  Each group of 4 students needs a 1-2” ball of playdough in four different colors.  For each group of 4 students, fill one paper cup ⅔ full of vinegar, another cup ½ full of baking soda, and a third cup ¼ full of sprinkles.  Prepare the “How Marine Fossils Were Discovered in Central Alabama” graph by dividing the chart paper into three columns.  (Click here for a sample graph.)  Label the bottom of the columns “They were moved here by other animals,” “They were left here when Alabama was under water millions of years ago,” and “Sharks and whales used to live on land.”  (If desired, you can divide the graph into 4 parts and label another column “other” so students who have a different idea can add these to the chart.)  Copy Gadsden Times Article (one per student).



  1. Show students one or more fossils found in Alabama or show the McWane Center fossil shark tooth collection. Tell students that the official state fossil of Alabama is an ancient whale and display the Encyclopedia of Alabama site. Ask students how shark teeth are found in central Alabama, far from the ocean.  
  2. Give each student a yellow sticky note. Have each student write his or her name on the note. Students should make a graph of their initial ideas about how the fossils were found in central Alabama by placing their sticky notes on the “How Marine Fossils Were Discovered in Central Alabama” chart. This graph can be used as an informal pre-assessment of their understanding about fossils and plate tectonics.


  1. Divide students into heterogeneous groups of 4. Ask, “What makes land change over time?” Have students discuss the question in their groups and share ideas with the rest of the class. 
  2. As students share ideas, expand on each one or add to their ideas by explaining that volcanoes can eject lava to form new mountains or rock formations, erosion and weathering can break down rocks by slowly washing them away and depositing sediment elsewhere to form new rocks, and the earth’s tectonic plates can move, making landforms rise or sink above sea level.
  3. Tell students they will model what happens when rock formations change over time. Distribute materials to each group: 1 cup vinegar, 1 cup baking soda, 1 cup sprinkles, 1 empty cup, 1 sheet blank paper, 1 toothpick, 4 balls of playdough in different colors, 4 straws, 1 plastic knife, and 1 paper towel. Have students sort the sprinkles into piles based on color.
  4. Ask students if they know what happens when vinegar and baking soda mix. (There is a reaction; it fizzes or foams up.) Tell students that they will mix vinegar and baking soda in the empty cup to simulate a volcano. The vinegar and baking soda they received should last for four “eruptions,” so caution students not to use all their materials at once.
  5. Place the empty cup in the center of the blank paper. Pour about a teaspoon of baking soda into the cup, then add vinegar until the cup starts to overflow. Once the reaction stops, trace around the puddle on the paper with a pencil. Dry the paper with a paper towel. Use one color of playdough to simulate the lava that erupted from the volcano. Cover the sides of the cup and the area inside the pencil line with a thin layer of playdough. This represents the igneous rock formed when the lava cools.
  6. Have students sprinkle one color of sprinkles over the playdough. This represents the plants and animals that lived during the time these rocks were formed. Press the sprinkles in slightly and discuss how some fossils are imprints left in mud that became rock over time, and other fossils are made of bones that fossilized over time.
  7. Repeat the “volcanic eruption” process three more times. Each time, the students should trace the outline of the eruption with a toothpick, add a different color of playdough to represent the new rock from the eruption, and add a different color of sprinkles to represent the plants and animals living during that time. Point out that the eruptions are not uniform; sometimes there may be a large area covered by the new rock and sometimes it may be a small area.  This means that sometimes fossils (sprinkles) from one time period will mix with those of another time period, and other times they will be separated by layers of rock.
  8. Tell students that rock can be worn away by moving water. Over time, a river or stream wears away the rock in its path. Have one student cut a path through all the layers of playdough to reveal the layers of rock stacked on one another. Ask which layers are the oldest (the bottom ones) and which are the newest (the upper ones).
  9. Have each student take a “core sample” by pushing a straw straight down through the layers of playdough. The playdough will stick inside the straw. By gently squeezing the straw right above the playdough, students will be able to extract a sample that contains several layers of “rock.”  Have students discuss the following questions in their small groups:
    • Did everyone’s sample look the same? Why or why not?
    • Did all the samples contain fossils (sprinkles)? Why or why not?
    • How could some samples prove that organisms lived here long ago, even if they are no longer found in this area? 


  1. Read Gadsden Times Article “Miles from Ocean, Creek Contains Reminders of Prehistoric Sharks.” (You may print this article for each student and have groups read the article together, or you can display the article for whole-class guided reading, depending on the needs of your students.)  
  2. Discuss how shark teeth could be found in North Alabama using evidence from the text. (For example, “During prehistoric times, the area around Tuscaloosa and points south was covered with ocean waters, greatly diminishing the chance of finding remains of the great dinosaurs that once ruled the earth.”)
  3. Give each student a blue sticky note. Students should write their names on the notes and post them on the “How Marine Fossils Were Discovered in Central Alabama” graph, forming a new column next to the blue pre-assessment column.  
  4. After discussing the ideas represented on the graph, have each student draw a picture and write a paragraph to explain how rock layers and the fossils show that the earth changes over time. Encourage students to include fast processes (such as volcanic eruption) and slow processes (such as erosion) in their explanations.


Assessment Strategies

The “How Marine Fossils Were Discovered in Central Alabama” chart serves as an informal pre- and post-assessment.

Students' individual written explanations serve as the summative assessment and can be evaluated using this checklist.  Point values may be assigned to each item on the checklist if desired.


Students can learn more about rocks, minerals, and fossils using interactive websites at  Students can also perform research by reading "Piecing Together Dinosaur Fossils" or "Dig" from (These articles are available for free but the teacher must create an account.) Following this research, have accelerated students present their learning to the class and/or serve as peer tutors.


Placing students in heterogeneous groups will give students access to peer tutors during the hands-on modeling activity and while reading the news article. In addition, students who have difficulty comprehending the main article may be provided with this alternate text from

Each area below is a direct link to general teaching strategies/classroom accommodations for students with identified learning and/or behavior problems such as: reading or math performance below grade level; test or classroom assignments/quizzes at a failing level; failure to complete assignments independently; difficulty with short-term memory, abstract concepts, staying on task, or following directions; poor peer interaction or temper tantrums, and other learning or behavior problems.

Presentation of Material Environment
Time Demands Materials
Attention Using Groups and Peers
Assisting the Reluctant Starter Dealing with Inappropriate Behavior
Be sure to check the student's IEP for specific accommodations.