Geologic Timeline Helper

I like to assign groups of about 4-5 students and have a relaxing art day from time to time. Having your students build a proportional geologic timeline on a large poster or paper roll is a great way to impress upon students how old the Earth is, and how briefly multi-cellular life forms, and humans in particular, have been around. Each group could build the entire thing or you could have each group do a particular period of time and assemble it at the end. Interesting things to note for each period are positions of the continents, atmospheric oxygen level, atmospheric carbon dioxide level, average surface temperature, sea level relative to today. All of this information is available in the Wikipedia links. Students figure out how long their timeline will be (the total age of the Earth) and then divide the timeline up into the major geologic periods. Drawings of representative organisms common to the period, and major Earth events (ice ages, comet bombardments, major extinction events) should be visually depicted.

Instructions: Enter a value (in inches or centimeters) for the total length of your geologic timeline, and the table will output the length (in your units) that each geologic period needs to be for proper scaling. For example, try values of 100 centimeters or 72 inches. Here's a great graphic with representative life forms. Click here or here to purchase the poster.

Total Length (inches, feet, centimeters, meters, etc) of your timeline:

Geologic Period Length of Period
Quaternary
Tertiary
Cretaceous
Jurassic
Triassic
Permian
Carboniferous
Devonian
Silurian
Ordovician
Cambrian
Proterozoic
Archean
Hadean
Total

Back to Geologic Timescale

Unit Converter


Grading: I use peer assessment when evaluating group work. I use a rubric to grade the group project, and a peer evaluation ballot for each group member to fill out privately, grading both themself and their peers. Although people new to peer assessment are sometimes skeptical, I have found that students, when given a rubric and graded work samples (from previous years' students), generally grade the projects of their peers objectively, and grade the work of their fellow group members accurately most of the time. I throw out the grades they give their own work, and the grade they give themselves as a group member if they are inflated, but I ask them them to self-evaluate in order to look for conflicts and get information about the group dynamic that I may not have observed.


Grade your own poster first. Assign each poster a grade by putting an x in the appropriate row. Circle your own group number. Responses are private.

Poster Grading Rubric Group Number
circle your own group #
Needs Improvement
(1)
Very Good
(2)
Exceptional
(3)

Biological Accuracy: free of factual errors, notes important events, depicts representative species correctly

1      
2      
3      
4      
5      
6      

Attention to Detail: free of technical errors (typos, calculation errors, missing information)

1      
2      
3      
4      
5      
6      

Visual Appeal: attractive and legible drawing, coloring, labelling

1      
2      
3      
4      
5      
6      
Groupwork: fair division of labor, equitable decision making, cohesiveness, good teamwork 1      
2      
3      
4      
5      
6      

 

List your group members alphabetically by lastname. Circle your own name. Put an x in the appropriate row to grade your work and the work of each of your group members.

Groupwork Grading Rubric

Group Members
list alphabetically by lastname, circle your own name

Needs Improvement
(1)

Very Good
(2)

Exceptional
(3)

Leadership: did the group member help determine the project's direction, or help build consensus?

       
       
       
       
       
       

Effort: did the group member pull their weight, and make a significant contribution?

       
       
       
       
       
       

Creativity: did the group member come up with any good ideas or suggest creative solutions to problems?

       
       
       
       
       
       
Cooperation: did the group member work well with the rest of the group or help resolve conflicts?