1. 2/19 & 2/ th Grade Agenda
Learning Objective: Discuss how radioactive dating can be used to date the age of rocks.
Collect HW: Reading & Notetaking p. 138 – 139
Change Jobs
Video: Walking w/ Monsters before Dinosaurs
Textbook Reading: p
HW: Reading & Notetaking p
Reminder Science Fair Board due 2/24 & 2/25(50 Points)

2. Reflection
Prompt: How can scientists know whether a rock is older than another rock?

3. New Jobs

4. Science Fair Project (50 Points)

5. Science Fair Project (50 Points)
Title: 3 points
Question: 3 Points
Hypothesis : 3 Points
Background: 3 Points
Materials: 3 Points
Procedures: 3 Points
Data Table: 3 Points
Graph: 3 Points
Bibliography: 2 Points
Results: 3 points
Discussion: 3 Points
Conclusion : 3 Points
Display Decoration: 5 Challenging: 5 Points
Scientific Validity: 5

6. What is an index fossil?
Index fossils help geologists match rock layer
To be useful as an index fossil, a fossil must be widely distributed and represent a type of organism that existed only briefly.

7. Which fossils are index fossils ?
Trilobite
Ammonite

8. These rocks are some of the oldest fossils in the world
These rocks are some of the oldest fossils in the world. How old are they?
Stromatolites: Remains of ocean reefs created by bacteria more than 3 billion years ago.

9. What is Radioactive Decay?
Radioactive Decay: over time, unstable elements break down or decay by releasing particles and energy.

10. What is half-life?
The half-life of a radioactive element is the time it takes for half of the radioactive atoms to decay.

11. If Geologic time went by in a single day, when did humans first appear?
Humans first appear one second before midnight

12. Geological Time Scale Paleozoic: Paleo means ancient or early
Mesozoic: Meso means middle
Cenozoic: Ceno means recent

13. Reflection
Prompt: Write 5 facts that you learned from the video.