Fossil Files Sub Guide Fossil Files Sub Guide
4-Day Instructional Plan • 4th Grade Science
4 DAYS
TEKS 4.10(A)
Explore and document evidence of past environments and organisms using fossils.
Key Vocabulary
Sedimentary, Body vs. Trace, Marine vs. Terrestrial, Preservation.
Daily 1-Hour Schedule
1
Formation: Fossil Foundations Packet
Focus: How fossils form in sedimentary rock layers.
Students read about burial and pressure, sequence fossil steps, and identify layers.
2
Past Worlds: Environment Explorer Packet
Focus: Marine vs. terrestrial clues and climate indicators.
Students act as detectives to determine if an area was once ocean or land based on finds.
3
Fossil Types: Trace and Body Packet
Focus: Differentiating remains (bones) from activity (tracks).
Students sort fossil types and analyze animal behavior through trace evidence.
4
Paleo Pro: Expert Analysis Packet
Focus: Synthesis of the week and final assessment.
Students complete a final review and design their own newly discovered fossil.
Classroom Management & Keys
Fast Finishers: Draw a "Dream Fossil" with its environment on the back of their packet.
Support: Allow students to work in pairs for Day 2 and Day 3 if needed.
Keys: All answers are in the "Fossil Master Key" document.
Collection: Please have students keep their packets until Day 4 for the final review.
Fossil Foundations Packet Fossil Files: Day 1
Ancient Burials & Formation
Name:
Date:
What is a Fossil?
Imagine a giant dinosaur walking near a river 70 million years ago. Suddenly, it dies. Most of the time, other animals would eat the body, or it would rot away. But sometimes, something special happens.
If the dinosaur is quickly covered by sediment (sand, mud, or silt), its bones are protected. Over millions of years, more and more layers of sediment pile on top. The weight of these layers turns the bottom sediment into sedimentary rock .
Slowly, water seeps into the bones and leaves behind minerals. These minerals turn the bone into stone! This process is called fossilization . A fossil isn't actually a bone anymore; it's a rock in the exact shape of the bone.
Activity 1: The Step-by-Step Fossil
Number the steps (1-4) in the correct order to show how a fossil forms.
Minerals replace the bone over millions of years, turning it to stone.
An organism dies and is quickly buried by mud or sand.
Weathering and erosion bring the fossil to the Earth's surface.
More layers of sediment pile on top, creating high pressure.
Activity 2: Fossil Investigation
1. Why is it important for an animal to be buried QUICKLY to become a fossil?
2. In which type of rock are fossils almost always found?
Igneous
Sedimentary
Metamorphic
3. Explain how "pressure" helps make a fossil.
Activity 3: Layers of Time
Layer A
Layer B
Layer C
Which layer is the YOUNGEST?
Which layer is the OLDEST?
Environment Explorer Packet Fossil Files: Day 2
Deep Sea Deserts & Environments
Name:
Date:
Clues to a Lost World
The Earth is always changing. Places that are deserts today might have been oceans millions of years ago. Fossils are photographs of the past. If a scientist finds a fish fossil in a desert, they know that area was once underwater.
Fossils also tell us about climate (how hot or cold it was). For example, finding palm tree leaf fossils in a cold place like Alaska tells us that Alaska used to be a warm, tropical jungle. Woolly mammoth fossils tell us an environment was very cold and icy.
By studying these clues, paleontologists can reconstruct what the Earth looked like millions of years before humans were ever around!
Activity 1: The Detective's Journal
Determine if each fossil indicates a Marine (ocean) or Terrestrial (land) environment.
A coiled ammonite shell found on a mountain top.
MARINE
LAND
A piece of petrified wood and a leaf imprint.
MARINE
LAND
A shark tooth and a fossilized sea urchin.
MARINE
LAND
A dinosaur nest with small fossilized eggs.
MARINE
LAND
Activity 2: Reconstruction
A scientist found coral fossils and giant clam shells in a rock layer in the middle of a forest. In the box below, draw what that environment looked like millions of years ago.
Activity 3: Climate Conclusion
Explain: Using evidence from the reading, how can a fossil tell us if an environment was hot or cold?
Trace and Body Packet Fossil Files: Day 3
Tracks & Bones: Fossil Types
Name:
Date:
Body Fossils
These are actual remains . They show what the animal looked like. Examples: bones, teeth, shells.
Trace Fossils
These show activity or behavior. Examples: footprints, nests, burrows, and fossil poop.
Activity 1: Type Detective
Write B (Body) or T (Trace) in the circles.
Dino Bone
Footprints
Dino Nest
Activity 2: Reading the Tracks
A scientist finds a set of large dinosaur footprints that are spaced far apart. Next to them, they find smaller footprints that are closer together.
1. Which dinosaur was likely moving faster?
2. Give one reason why you think that:
3. Why are trace fossils often MORE useful than body fossils for studying animal BEHAVIOR?
Expert Analysis Packet Fossil Files: Day 4
Expert Analysis & Final Review
Name:
Date:
Part 1: Key Concepts
1. In which rock layer would you find the OLDEST fossils?
A. The top layer
B. The bottom layer
C. The middle layer
D. Rocks don't have layers
2. Which of these is a TRACE fossil?
A. T-Rex skull
B. Mammoth tusk
C. Dinosaur footprint
D. Petrified log
3. What is the first step in fossil formation?
A. Minerals turning bone into stone.
B. An organism being quickly buried by sediment.
C. An earthquake bringing rocks to the surface.
Part 2: Field Analysis
"At a dig site in West Texas, scientists found fossilized seashells in a bottom rock layer. In the layer directly above it, they found fossils of fern leaves and dinosaur tracks."
1. Describe how the environment changed over time at this site:
2. What evidence supports your answer above?
Part 3: The Discovery
Imagine you have discovered a BRAND NEW fossil! It has sharp teeth, webbed feet, and was found in limestone with fish skeletons.
Give your fossil a name:
Environment (Marine or Land?):
Diet (What did it eat? How do you know?):
Sketch your discovery
Fossil Master Key Fossil Master Key
Answer Key for Days 1-4 • 4th Grade Science
Day 1: Fossil Foundations
Activity 1 (Sequence):
Activity 2 (Investigation):
Activity 3 (Layers):
Day 2: Environment Explorer
Activity 1 (Sorting):
Written Reflection:
Day 3: Trace and Body
Activity 1 (B vs T):
Activity 2 (Behavior):
Day 4: Expert Analysis
Part 1: 1: B, 2: C, 3: B
Part 2 (Analysis):
Part 3: Answers will vary. Must identify Marine based on webbed feet/fish skeletons. Teeth suggest diet (meat/fish).
