I wrote this lesson plan for my EDCP 349 project and I just had so much fun with it that I wanted to include it on my personal blog! It’s just too good to hide under the password protected world of Connect 😉 I’m planning on teaching it on my 10-week practicum, so I’ll update it later with notes on how it goes with actual kids, not just BEd test subjects!
Science in the Yard – Geologic Time Machine
Grade: 6/7 Time: 5 – 60 min. Subject: Science
Curriculum
BC Curriculum 2016 Grade 7 Science
• Big Idea: Earth and its climate have changed over geological time
• Content: Fossil records and geological dating.
Purpose
• To explore the concept and scale of geologic time.
• To think about changes that have happened to the Earth since it’s beginning up to the present day.
Learning Intentions
• Students will be able to describe the idea that major events and changes on Earth have happened over huge periods of time (ie. millions and billions of years).
Materials
• 1 metre stick or shop tape measure.
• 6 markers – 1 for each major Earth event represented on the timeline.
Instructions
1. Place metre stick or shop measuring tape set to 1 metre down on the ground. 1 metre will represent 100 million years.
2. Place a marker at two measurements:
1. 2 mm – Evolution of modern humans, representing approximately 200, 000 years ago
2. 2.5 cm – Evolution of homo habilis, our early human ancestor, representing approximately 2.5 million years ago.
3. Have a student volunteer measure their longest stride to the metre measured on the ground. Have them use a step roughly that length to measure each new segment of our timeline.
4. Moving forward on the timeline, place markers at the following points:
5. 2 metres (200 million years ago) for break up of Pangaea, and 2.7 metres (270 million years ago) for the formation of the supercontinent Pangaea.
6. 2.3 metres – the approximate evolution of dinosaurs and mammals, 230 million years ago.
7. 6 metres – The approximate evolution of the first multicellular organisms, 600 million years ago.
8. 35 metres – The first organisms evolve (ie. single cell organisms), 3.5 billion years ago.
9. 46 metres – the origin of the Earth, 4.6 billion years ago.
Discussion
Discussion questions to conclude the activity could be as follows (though they are certainly not limited to these!):
• In thinking about the origin of our early ancestors (both homo sapiens and homo habilis) we’re going back very far in time. Yet on our super-shrunk-down timeline these two events look miniscule! What does that say about the age of our Earth? What about human existence on Earth?
• Although Pangaea is perhaps the most famous past arrangement of the Earth’s crust, the continents have been in many different formations over time. What does this make us wonder about changes on the Earth’s surface that have happened over 4.6 billion years? Do you think it has changed a lot?
• How would the Earth have been different when homo sapiens first appeared? Homo habilis? The first animals? The first organisms? What would these creatures have looked like? What conditions would they have needed to survive? What would it have felt like to breathe Earth’s air and swim in an Earth ocean 600 million years ago? 3.5 billion years ago?
• Think about how much time passes between events like the first single cell organisms and the first multicellular organisms evolving on Earth. What does this make you think about some of the rapid changes (particularly in our climate) being observed on the Earth today?
Scientific Explanation
When thinking of events that have occurred during Earth’s history, we’re engaging with the concept of geologic time – a timeframe that is so vast that it virtually incomprehensible to imagine from our human perspectives. The point of this exercise is to highlight how major changes to the Earth took millions and billions of years to occur.
Even the concept of geologic time is complex, as we are describing events that have estimations and margins of error of millions of years. Even the partitioning of time into eons, eras, periods and epochs makes these borders seem very tidy and contained, when really changes to the Earth and it’s inhabitants occur based on conditions that can take develop slowly, over countless permutations, and by chains of events that are interconnected.
This brings us to think about what our role as inhabitants on this planet (if only for the past 200, 000 years) is? If we think of the timescale on which changes tend to occur naturally on Earth and how quickly changes seem to be happening in the present day, especially with regards to climate change? How should we look at human practices that are invasive to the Earth and the effects they are triggering, such as massive deforestation and fracking? The Earth has gone through many changes in climate, geography, inhabitants, etc., but is there something to be said for the rapid changes that we can observe even in our human lifetimes when we compare it to a much larger span of time that events have occurred in Earth’s past.
In My Own Words (for Grade 6 and 7 students)
When we read about the ages of fossils or events such as the formation of the Earth, it can be challenging to think about how incredibly long ago these events were. We’ve read in our textbooks and heard a lot about big stages in the history of the Earth, such as the formation of Pangaea, or when animals that are now fossilized such as trilobites lived. It can be hard to grasp just how long ago from human existence these events were.
An important thing to keep in mind while thinking about events over geologic time is that events don’t have exact dates like you might think about your birthday, or the flight of the first airplane. Some of the most accurate predictions of when certain changes happened are only accurate within plus or minus several millions of years. Nor would these changes have taken place overnight. The first organisms didn’t just magically appear one day! There would have been a long process of change and adaption and certain conditions being present over a long period of time for the evolution of things to happen.
When we think about the very long amount of time that it can take for changes to naturally occur on the Earth, what does this make us wonder about the changes to the Earth that we’ve heard that are happening to the Earth, such as climate change? Humans have been around for a very small amount of time in comparison to the age of the Earth, but we have learned about many changes that are occurring quite rapidly in our presents times, such as global warming. What role do you think humans play in these events? Do we help the Earth? Hurt the Earth? Do we do both these things sometimes? We’ve seen a snapshot from this activity that the Earth has changed a lot over time, so what does this make us think of some of the very rapid changes that are happening on Earth today?
References
Encyclopedia of Britannica (n.d.). Pangaea: supercontinent [web page]. Retrieved from: http://www.britannica.com/place/Pangea.
New Scientist (n.d.). Timeline: Human Evolution [web page]. Retrieved from: https://www.newscientist.com/article/dn9989-timeline-human-evolution/
The Teaching Channel (n.d.). History of the Earth
. Retrieved from: https://www.teachingchannel.org/videos/teaching-geological-time
University of California Museum of Paleontology (n.d.) Geologic time scale [web-based timeline]. Retrieved from: http://www.ucmp.berkeley.edu/education/explorations/tours/geotime/guide/geologictimescale.html
Reflection
Why did you choose this experiment and topic?
I chose to explore geologic time for two main reasons. The first is that I will be teaching a unit in my grade 6/7 class on geology and the history of the Earth, so I wanted to plan a lesson that would be usable in my practicum. The second is that, with that practical consideration in mind, I wanted to pick a topic that I felt could benefit from some lively illustration. My experience as an Anthropology major prior to the education program was that talking about events in distant ancient times can be kind of mind-boggling, but it is really essential to understand the scale of these events in order have a platform to discuss changes to the Earth. I can remember trying to wrap my mind around concepts such as 2 million year old fossils as a younger person and not really “getting it” because it’s really hard to visualize numbers that large in any practical sense. Hence, the idea for a tangible timeline to illustrate the scope of geologic time and just how far apart events take place was the idea I settled on.
Why do you think the above criteria were chosen for this assignment?
I thought the criteria for the lesson was fantastic! So fantastic that I want to apply it to all of my subjects, not just Science! Over the years that I have worked with children I had really begun to notice how much time children spend inside and how many non-reusable or non-recycled materials are used in designing activities for children. I felt discouraged that learning seemed to be inherently wasteful, especially in materials-rich subjects like Science and Art. I also found that the children I worked with would often complain about going outside because they simply aren’t as used to it as I was as a child. Finding more ways to cut down on waste, promote green methods in the classroom and get outside can be really beneficial to keeping the environment at the forefront of all subject areas.
What and whom did you consider when you composed your ‘explanation’?
Composing my explanations was actually a bit challenging for me because I would personally want to use as much scientific language with my grade 6/7s as possible. When working with older students I want them to use as much scientific language as they can because they’re at the point where I believe they’re ready to use it and start engaging with it. However, my end result with the two explanations was one that I felt would be really good when actually conducting the experiment so that the students aren’t also focusing on deciphering the new scientific vocabulary while interacting with the model, but I would want to later have them do a follow-up activity that engaged some of the scientific language (particularly epochs and eras) so that they could tie that in to their learning.
What surprised you about the ways your peers responded to you experiment on SITY day?
I wasn’t exactly “surprised” when it happened, but I really hadn’t thought about how my peers might actually get to my conclusions before I did. I think each group actually made the jump to connecting the final reveal of the model to climate change before the words came out of my mouth – I typically only got as far as just pointing out where humans were on the timeline before someone made the connection and basically said my next point for me. Which was great! I was really pleased that the model connected with folks enough that they were able to see some of the points I wanted to highlight without me having to say it! In future I think I’ll ask my students questions about what they think about the model before I even throw any prompts in to allow them to make the connections for themselves since I think that would make it even more meaningful.
What worked well? What would you do differently next time?
What worked well was how the model got people excited and engaged with the idea. The materials were also really simple, so it was really easy to take outside. What I could have done better in the context of the SITY was stay focused on one idea to highlight on the timeline each time so that my ideas were a little more focused – however, the activity is really best suited for a whole lesson where the students could spend lots of time discussing and exploring different events on the timeline (so many more could be added!) and really getting a sense for geologic time from multiple angles.
How do you interpret this assignment and activity as a Teacher Inquiry?
It was a great opportunity to try something a little outside the box! When talking about geologic time, we often rely on textbook based diagrams and timelines that just aren’t very engaging – but interactive timelines are just so cool! It was a great way to explore different ways to incorporate a lesson with getting kids moving outside. It was so easy to do (in fact, I think I illustrated my point easier with the outdoor timeline with much more ease than I could have with a paper-based or indoor timeline), so it was really encouraging for helping me think about other ways that I could bring my practice and classes outside!