The Arizona STEM Acceleration Project

Just a Second

Just a Second -

Geological Time Scale

A 8th grade STEM lesson (2 days)

Katherine Otwell

1-31-24

Notes for teachers

List of Materials

• Book “Just a Second” by Steve Jenkins. LINK to book read online
• Handout My Personal Timeline
• Handout Geologic Time Scale as a Calendar Year - Make copies for each group of 4 of a 12 month calendar and laminate.

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• Student computers to go to National Park Service - Geologic Time Scale
• Geologic Column Lab with student handout to cut/color. Scissors, glue, copy paper and colored pencils. Copies of activity for each student.
• Copy for each student on the PERFORMANCE ASSESSMENT.

Notes

• This is a lengthy activity and could take more than two days, but it can be scaled down also.

Standards

Az Science Standard 8.E1U1.6

Analyze and interpret data about the Earth’s geological column to communicate relative ages of rock layers and fossils.

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MS-ESS1-4. Construct a scientific explanation based on evidence from rock strata for how the geologic time scale is used to organize Earth's 4.6-billion-year-old history.

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Science and Engineering Practices Constructing Explanations and Designing Solutions Constructing explanations and designing solutions in 6–8 builds on K–5 experiences and progresses to include constructing explanations and designing solutions supported by multiple sources of evidence consistent with scientific ideas, principles, and theories.

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Standards

• Construct a scientific explanation based on valid and reliable evidence obtained from sources (including the students’ own experiments) and the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future.

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Crosscutting Concepts: Scale, Proportion, and Quantity Time, space, and energy phenomena can be observed at various scales using models to study systems that are too large or too small.

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Standards

ELA/Literacy

RST.6-8.1 - Cite specific textual evidence to support analysis of science and technical texts.

WHST.6-8.2 - Write informative/explanatory texts, including the narration of historical events, scientific procedures/ experiments, or technical processes.

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Standards

Mathematics

6.EE.B.6 - Use variables to represent numbers and write expressions when solving a real-world or mathematical problem; understand that a variable can represent an unknown number, or, depending on the purpose at hand, any number in a specified set.

7.EE.B.4 - Use variables to represent quantities in a real-world or mathematical problem, and construct simple equations and inequalities to solve problems by reasoning about the quantities.

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Objectives:

Day 1:

• Understand and demonstrate geologic time scale.

Day 2

• Construct a scientific explanation based on evidence from rock strata about Earth’s 4.6 billion year history.

Agenda (2 days)

DAY 1:

ENGAGE (10 MIN)

1. Read “Just A Second”

EXPLORE (20 MIN)

1. Complete the Personal Timeline Activity

EXPLAIN (25 MIN)

1. Watch video “Big Idea 2: Earth is 4.6 Billion Years Old”

2. Complete a geologic time scale as a calendar year activity.

DAY 2:

ELABORATE (20-30 MIN)

1. Geologic Column Lab - handout to cut and color.

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Agenda

EVALUATE (20-30 MIN)

1. This may take the beginning of the next class to finish. It is from The Wonder of Science and does a great job of evaluating what is learned in this lesson.

PERFORMANCE ASSESSMENT

Students will need a copy of the performance assessment and a sheet of notebook paper unless they complete it on their computer.

Driving Question

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How can geologists piece together Earth's past and place major events in order using only clues that were left behind?

ENGAGE

1. Ask the question “How old is Earth?” Allow students to take guesses of how long Earth has been around.
2. Ask students “How long ago were dinosaurs on Earth?” “How long has humans been on the Earth?” “How do you think geologists figured out what was on Earth and when?”
3. Watch or read the book “Just A Second”
4. Students can be grouped for these discussions and you can create a driving questions board, if you choose. Each group can report out their findings on a sticky note and place them under these questions or other questions the class comes up with.

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EXPLORE

1. Provide each student with a copy of MY PERSONAL TIMELINE sheet. Follow the directions on the document.
2. Students will follow the directions on the activity sheet to create their own geologic time scale based on events in their lives.
3. Students will work independently for this activity. However, allowing them to compare each other’s personal life events is great!

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EXPLAIN

1. Watch video “Big Idea 2: Earth is 4.6 Billion Years Old”
2. Complete a geologic time scale as a calendar year activity. See directions at the top of the activity sheet.
3. Now that the students have some perspective how how long Earth has been around you should ask them “How does a geologist find clues to where things belong in Earth’s timeline?” How do they see what’s beneath their feet and put it where it belongs in time?

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ELABORATE

1. Students will complete the Geologic Column Lab. This can be done individually or with a partner. You will need copies for each student.
2. You will need colored pencils, scissors, glue and a sheet of copy paper to glue activity to. Questions can be done on a sheet of notebook paper.
3. After they’ve had time to completed the activity, you can have a class discussion on the analysis questions, and write a paragraph summary.

(Optional) Conclusion:

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Write a paragraph that explains how rock layers and fossils that may be found in completely different locations can still be used to piece together a more complete record of geologic time. How does this tell us about evolution? With this in mind, write a second paragraph that explains your own geologic column, from the bottom to the top. This should include a rundown of environmental changes and the species (symbols) that evolved and went extinct over the course of geologic time.

EVALUATE

1. Students will use the documents linked here to write a CER (Claim, Evidence and Reasoning). This is provided by the website The Wonder of Science. All of it does not need to be completed. Part of it can be used as an extension or even a remediation activity. It uses artifacts as evidence to have students justify their claim.
2. Each student will need a handout of the activity. You may want to complete it on notebook paper or online.

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PERFORMANCE ASSESSMENT

Differentiation

If students are struggling with a CER, The Wonder of Science website has a great video/activity below on how to break down this strategy.

CONSTRUCTING EXPLANATIONS

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Remediation

Remediation

Thinking in Scale can often be baffling for adults and children. That is why I spent so much time on this topic. However, if students are still struggling here are some activities for them to try from The Wonder of Science.

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Differentiation

Extension/Enrichment

Option 1:

The evaluation in this lesson could be used as an enrichment, and the conclusion from the the Geologic Column Lab could be used for assessment along with the analysis questions. In other words use the performance assessment for the enrichment tool.

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Option 2:

You can go to the NATIONAL PARK SERVICE WEBSITE, and have students choose the way the want to express the geologic time scale, and have them check out other topics related to the geologic time scale.

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My Personal Timeline

This is just a screenshot of the first page. Click on the links to open a “copy” of the document.

Geologic Time Scale as a Calendar Year activity

Geologic Column Activity

In this video a teacher has explained to her students how to do this lab and it shows what the resulting cut out should look like. It may be helpful to preview.

VIDEO OF COMPLETING THE LAB

Performance Assessment