Natural Selection: Discovery

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Objective

Students will be able to uncover some of the important questions that surround the theory of evolution and natural selection.

Big Idea

How did the elephant get its trunk?

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Purpose of Lesson:

The purpose of this lesson is to gather information about student understanding and give students a chance to ask important questions that might guide our thinking during the unit.

 

Major Strategies to Watch for:

1) Pre-assessment probe - This quick pretest is a great way to gather information and thinking from your students.

2) Table Top Blog - This collaborative questioning and writing technique allows students to quickly generate ideas and come into contact with lots of new ideas. 

3) Question Matrix - The Question matrix allows students to ask higher level questions which can lead to more interesting discussions and conversations.

Ready. Set. Engage!

5 minutes

Learning Goal: Uncover important questions about life?

Opening Question:  How did the elephant get its trunk?  

Students record their opening question on their learning goal sheet and are ready to start class 3 min after the bell has rung.  I reward students who get started early with ROCK STAR SCIENTIST tickets.  

Follow the links to learn more about the beginning of class strategies and ROCK STAR scientist tickets.   

Hook

5 minutes

The purpose of this section is to dramatically introduce the topic of natural selection in an engaging format.  

I really love the series of videos by Frank Gregorio on YouTube. I use his Introduction to Evolution video in this lesson. I think he does a great job on crafted intriguing videos with dramatic music in a way that makes kids curious. For these videos, I simply ask the students to read the words and concentrate on the images.

At the end of the video, I ask them what jumped out at them and what they were curious about.  

Pre-assessment

5 minutes

I start this unit with a probe (pre-assessment). 

A group of rabbits were moved from a warm climate to a cold climate.  What do you think happened?"

A- The animals adapted to the cold.

B- The animals decided to move back to the warm climate.

C- The animals didn't adapt and were cold a lot.

D- The animals didn't adapt and froze or starved.

When I examined my data more than 75% of students chose answers A and B. This really indicates that students have a deep misunderstanding of the word adapt. This isn't really surprising, think about how many times we say things like, "You just need to adapt."  

Some of my students responses really illustrate this thinking. I'm retyping them here without spelling errors to distract us from their thinking ;>).

  1. When the rabbits move they can just grow a thicker coat that will help them adapt to the new place, like a cat.
  2. Because animals do whatever they can to survive and get  food and shelter. Animals adapt by learning what it feels like and learning what the new environment is.

Of all the misconceptions around this one is one of the hardest to fix. It is important to continue to gather data over time to check and see if their ideas are changing.

Discovery Activity

20 minutes

The purpose of this section is to elicit student ideas and most importantly questions. I use a question matrix that I found in Higher Level Questions by Spencer Kagan and have students write on tabletop blogs. Tabletop blogs are ridiculously easy to make and yet very engaging to students. You simply get several pieces of butcher paper out and put one piece on a table. Place some markers at the table for student writing and you are good to go! 

For this activity, I am using tabletop blogs to have students generate a wide variety of high level questions for the unit on evolution. Along with the butcher paper and markers, I also put several copies of the question matrix at each table. Some teachers like students to have a simple blank page in front of them. I find that students have a tendency to freeze and not be able to generate questions without some hook or scaffold. For this activity, I like to tape color pictures of different environments on the paper.  

I first have the students write down some observations about the picture.  For example:

  1. There are different kinds of trees.
  2. There is a monkey.
  3. I see a river.

Then I ask the students to generate questions using the question matrix about where the plants and animals came from and why they look the way they do. Some of the questions my students came up with for this picture were:

  1. Why are the birds brightly colored?
  2. What makes the leaves of the front plant so big?
  3. What makes the tree trunks so large?
  4. How might the animals interact?

After about 5 minutes total, I ask the students to move to the blog of a different environment. (If students are still working intensely I give them more time.)

At the next blog they repeat the process. However, they aren't allowed to repeat observations or questions.  This pushes the students to go deeper into the pictures than their first impulse thoughts. We continue for about 20 minutes, visiting the different blogs and making observations and writing questions.  

One way to build more accountability into this activity is to have students initial their observations and questions. This gives the students the impression that their work will be personally reviewed even if you don't plan to read them that closely. I find that this leads to better quality work. 

I put some alternatives in the screencast below.

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Discussion

7 minutes

The purpose of this discussion is to decide which questions were the most interesting and start having some class discussions.

I start this off by having students visit the tabletop blogs again, this time putting stars by the questions they thought were the most interesting.  If you have never had students evaluate questions before, it is worth stopping here and having a discussion about what makes an interesting question.  I tell students that good questions are:

  1. Not yes or no
  2. Not "googleable"
  3. Interesting and connected

Once students have starred their favorites, we put those questions on an anchor chart.  I use this anchor chart both for the discussion today and to guide our thinking during the unit.  

I ask students to choose a question to discuss in their groups.  Then, I ask them to take out their writing to think notebooks and write for two to three minutes about their thoughts.  Writing to think is a great strategy to help students verbalize and process their thoughts.  In my classroom, students are trained to write for the entire time period.  If they are having trouble thinking of what to say, I tell them to simply write words down.  Often that will spark a new thought. Another way to kickstart then is to suggest they "tell you", and after they've talked for a short while, point out that they do have thoughts to record.

Now that students have had a chance to think and write, we start the discussion.  Students should use the discussion sentence starters on the anchor chart from class.

 I stand in the middle of the tables and use Class dojo to give positive feedback to students and hold them accountable for their conversations.  I have found that this GREATLY enhances the quality and quantity of talk at the tables.

If students finish with their first question and still have time left, I ask them to repeat the process with another question.

Closure

2 minutes

Closing Statement: Today we asked questions about species change and evolution.  Tomorrow we will be learning some important terms for our unit of study.

Closing Question:  What does evolution mean to you? 

Closure depends greatly on timing and is not as easy to plan in advance as opening.  You can find more information about how I manage closure here.