Teaching Sequence

Work through this resource material in the following sequence:

15 minutes	Part A: New Discoveries
15 minutes	Part B: Classifying Using Common Features
20 minutes	Part C: Using a Dichotomous Key
5 minutes	Reflection

Introduction: Flipped Classroom

Prior to participating in this lesson, students should complete the following flipped classroom activity. This activity is also available on the Student Worksheet.

In this activity:

Students will look at the following range of vocabulary words:
- Organism
- Species
- Classification
- Dichotomous
- Abdomen (insect)
- Elongated
- Transparent
For each word students will need to reflect on and respond with the following:
- I have not seen this word
- I have seen this word
- I can use this word in a sentence
- I could teach the meaning of this word to another student
For any words where students chose ‘I have not seen this word’ or ‘I have seen this word’, students will need to use a resource such as a dictionary, an adult, or a trusted classmate, to find out and record the meaning of the word.
For any words where students have chosen ‘I can use this word in a sentence’ or ‘I could teach the meaning of this word to another student’, students should use a dictionary to confirm their understanding and then find someone who answered ‘I have not seen this word’ or ‘I have seen this word’ and teach them the meaning.

Part A: New Discoveries

Step 1.

Begin this lesson by going over the vocabulary from the lesson introduction. Invite students to explain what each word means and use it in a sentence.

Examples:

Vocab Word	Definition	Sentence Example
Organism	Any life form	Plants and bacteria are both organisms.
Species	A group of organisms that can interbreed and produce fertile offspring	A chihuahua and a great dane, though very different, are the same species.
Classification	A system that groups organisms based on similarities.	Classification helps us know that a catfish is not a type of cat.
Dichotomous	Dividing into two branches	A dichotomous key identifies an organism by narrowing down characteristics.
Abdomen (insect)	In an insect, the abdomen is the third segment in the main body (Segments: head, thorax and abdomen)	The abdomen of a dragonfly is very long.
Elongated	Long and thin	A dragonfly has an elongated body shape.
Transparent	Can be seen through	Some insect wings are transparent.

Step 2.

Guide the class through the following scenario:

Think of an animal. Picture it in your mind and think about how it looks, moves, eats, behaves. Now think of characteristics that you can add to it or change to make it even better at a specific task, e.g. longer legs to jump further to catch prey. This will be a subspecies of your original animal. A subspecies is kind of like a step towards a group of animals becoming a new species. It is genetically similar enough to the original species that they could interbreed, but it has characteristics that are unique.

Step 3.

Ask students for the characteristics they thought of to adapt their original species. Write these characteristics on the board.

Step 4.

Inform the class that we can group species using common features. Have the class point out features that can be grouped - for instance, we might group extra legs and extra arms together, as they both involve additional limbs.

Step 5.

Instruct the class to put up their hand if their original species was an insect. Ask students to reflect on why they did or didn’t choose an insect. This might elicit responses such as; they dislike insects, their favourite animal is something different, or the first thing that came to mind was something different. Explain that the majority of newly discovered species in the world are insects. Australia has an estimated half a million undiscovered species, many of which will be insects.

Step 6.

Tell the class that you will be showing pictures of subspecies discovered in Australia. Their job is to decide what type of organism the subspecies is.

Write the following options on the board:

Spider, ant, worm, caterpillar, springtail, slug, nudibranch, moth, dragonfly, lacewing, fly, bee.

Scaffolding Tip: If students don’t know what some of the options are, reassure them it is okay to guess. If the class has very little prior knowledge of the options then you can group them according to similarities:
- Group 1: spider, ant.
- Group 2: worm, caterpillar, springtail, slug, nudibranch.
- Group 3: moth, dragonfly, lacewing, fly, bee.
  The class can then decide on a group and guess which option each creature would be within their group.

Step 7.

Project the Bush Blitz photos of the subspecies discoveries.

For each photo, read out each type of organism on the list (eg “Is this a spider? Is this an ant?”). Instruct the students to raise their hands if they think the photo shows that organism. Note which organism was most difficult for students to decide on by drawing a star next to its name.

Step 8.

Ask the class: Why is it difficult to determine what something is from a photo? What other information would you need?

Possible answers: location found (tree, grass, water), how large it is, is its body soft or hard?

Part B: Classifying Using Common Features

Step 1.

Display the following dichotomous key on the board (also available on the Student Worksheet).

Vocab reminder: Dichotomous. Dicho means ‘apart’, after the Ancient Greek dikha (compare divide), and tomous, from the Ancient Greek tamno, meaning ‘I cut’.

Dichotomous Key

1. a) Soft body b) Hard body	……………………………………………Go to 9 ……………………………………………Go to 2
2. a) 6 legs b) 8 legs	……………………………………………Go to 5 ……………………………………………Go to 3
3. a) Smooth-looking body b) Hairy-looking Body	……………………………………………Ant-Mimicking Spider ……………………………………………Go to 4
4. a) Colourful, raised abdomen b) Small, dark abdomen	…………………………………………....Peacock Spider ……………………………………………Jumping Spider
5. a) One pair of wings b) Two pairs of wings	……………………………………………Bee Fly ……………………………………………Go to 6
6. a) Short body b) Elongated body	……………………………………………Go to 8 ……………………………………………Go to 7
7. a) Large, mantis-like front legs b) Thin front legs	……………………………………………Mantispid Lacewing ……………………………………………Dragonfly
8. a) Furry wings b) Semi-transparent wings	……………………………………………Woolly Bear Moth ……………………………………………Teddy Bear Bee
9. a) Has a shell b) No shell	…………………………………………….Semi-slug …………………………………………....Go to 10
10. a) Long body b) Short body	…………………………………………....Velvet Worm ………………………………………...….Go to 11
11. a) Uniform appearance b) Various shapes on body	…………………………………………….Springtail …………………………………………….Nudibranch

Step 2.

Tell students they have two minutes to discuss with a partner what they think the key is for and how it is used.

Step 3.

Choose one subspecies image to project on the board. Inform the class that they and their partner have five minutes to attempt to use the key to classify it. They will need to use the information provided, the picture, and their problem-solving skills to figure out how to use the key on this subspecies.

Step 4.

After five minutes, or when everyone is finished, go through how to use the key, and students can compare their results to yours.

Literacy scaffolding: Explain how to interpret a paragraph of information. An unbroken piece of Tett can be difficult to analyse. Look for and circle key words or words you think are important. Try to find those words on the key. Alternatively. look at words on the key and try to find it in the text. Make sure you also circle phrases such as 'does not have' or 'does not contain'.

Part C: Using A Dichotomous Key

Step 1.

Now separate the class into groups of three to four students and set them up at four stations, and provide each station with a key and the picture and information for three of the animals.

Then provide students with these instructions for the activity:

As a group, you must use the dichotomous key to classify each animal.
Once you have decided what the animal is, you will write its name under its image.
Do this for each animal you have been provided.

After five minutes, or once the groups have finished, instruct each group to leave their key and images at their station and move to a new station. Inform them they must classify each animal on the new station and see if their group agrees with the name written under the image. Tick beside it if you agree and put an X beside it if you don’t.

Rotate students around each of the three tables.

Step 2.

Then instruct students to return to their original station and ask the class if anyone disagreed with their classification.

On the board, use the key for any of the animals that groups disagreed on if any.

Finally, congratulate the class on their scientific rigour. Science is subject to peer review, which means other scientists check the work for accuracy.

Reflection

Instruct the students to individually answer the reflection questions on their worksheets:

Why do scientists use dichotomous keys to classify organisms?
Potential answers: To make it easier and quicker to determine what organism they have found. To be able to compare a large range of organisms easily.
Note down any vocabulary from the lesson that is new to you or you are not confident using. Use a dictionary to find out their meanings and create a sentence for each word.

Differentiated Learning

Extension -

Instruct students to choose any animal and create their own dichotomous key. They can then swap with another student and have them use the key to classify their animal.

Provisions for Learning Support -

Students may need more guidance using the key. During Part C the teacher can group students in ability levels, then stay with the group that needs the most support.

Teacher Reflection

Take this opportunity to reflect on your own teaching:

What did you learn about your teaching practice today?
What worked well?
What didn't work so well?
What would you share?
Where to next?
How are you going to get there?

Backyard Bush Blitz - Identification Keys

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