Materials

• Table 7.4.
• Meter stick or measuring tape
• Rope or yarn (at least 5 m length)
• Masking or painter’s tape
• Markers
• Index cards

Procedure

1. Cut rope for a timeline
   
   1. Measure out and cut 4.6 m of straight rope or yarn.
   2. This 4.6 m length of rope will represent the entire 4.6 billion years since the formation of Earth.
   3. Wrap the two rope ends with masking tape to prevent fraying.
       
2. Label one end of the rope as “present day” and the other end as “4.6 billion years ago.”
    
3. Use the meter stick to measure 0.5 m from the present day end of the rope.
    
4. Use masking tape to label this 0.5 m point as “500 million years ago.”
    
5. Continue measuring and labeling rope segments, in 500 million increments, until the end of rope.
    
6. Prepare event index cards
   
   1. Complete the missing cells in the list of several major events in Earth’s history (Table 7.4.).
   2. On one side of a blank index card, write the name of the event and a brief description of it.
   3. Write the event date on the opposite side of the index card.
       
7. Attach event index cards to the timeline at the appropriate locations.
    
8. Present your timeline to your classmates.