Sustain the chain
View Sequence overviewStudents will:
- identify evidence of a decomposer on fruit.
- explain the role of a decomposer in a habitat.
Students will represent their understanding as they:
- identify the sequence of decomposing fruit.
- describe the effects of a decomposer.
In this lesson, feedback is formative.
Feedback might focus on:
- Can students identify the sequence of decomposition?
- Have students identified signs of a decomposer being present?
- Can they separate a claim from the evidence?
Whole class
Class science journal (digital or hard-copy)
Materials to create a word wall
The video Fruit and vegetable decomposition, Time-lapse (1:36 min)
Low tech option: digital camera
High tech option: time lapse camera (for example, a GoPro)
Each group
Small trowel or shovel
Gardening gloves
Small clear plastic container with a sealable lid (once this is used, it should not be opened again)
Magnifying glass
A cut up piece of fruit (apple, berries, orange)
Each student
Individual science journal (digital or hard-copy)
Decaying fruit Resource sheet
Lesson
The Inquire phase allows students to cycle progressively and with increasing complexity through the key science ideas related to the core concepts. Each Inquire cycle is divided into three teaching and learning routines that allow students to systematically build their knowledge and skills in science and incorporate this into their current understanding of the world.
When designing a teaching sequence, it is important to consider the knowledge and skills that students will need in the final Act phase. Consider what the students already know and identify the steps that need to be taken to reach the level required. How could you facilitate students’ understanding at each step? What investigations could be designed to build the skills at each step?
Read more about using the LIA FrameworkRe-orient
Remind students of the Roo survival game from the previous lesson.
Discuss:
- What did the kangaroos need to survive?
- What happened to the number of kangaroos when there was not enough food?
- What type of food do kangaroos eat to get energy?
- Grass, trees, producers.
- Where do producers get their energy?
- Light/heat from the sun.
- How will this affect the local bushland/school vegetable garden/compost bin we are creating?
The Inquire phase allows students to cycle progressively and with increasing complexity through the key science ideas related to the core concepts. Each Inquire cycle is divided into three teaching and learning routines that allow students to systematically build their knowledge and skills in science and incorporate this into their current understanding of the world.
When designing a teaching sequence, it is important to consider the knowledge and skills that students will need in the final Act phase. Consider what the students already know and identify the steps that need to be taken to reach the level required. How could you facilitate students’ understanding at each step? What investigations could be designed to build the skills at each step?
Read more about using the LIA FrameworkIdentifying and constructing questions is the creative driver of the inquiry process. It allows students to explore what they know and how they know it. During the Inquire phase of the LIA Framework, the Question routine allows for past activities to be reviewed and to set the scene for the investigation that students will undertake. The use of effective questioning techniques can influence students’ view and interpretation of upcoming content, open them to exploration and link to their current interests and science capital.
When designing a teaching sequence, it is important to spend some time considering the mindset of students at the start of each Inquire phase. What do you want students to be thinking about, what do they already know and what is the best way for them to approach the task? What might tap into their curiosity?
Read more about using the LIA FrameworkIntroducing decomposing
Pose the questions:
- What happens to a piece of fruit if you don't eat it? Does it stay 'good' forever?
- What happens to the flowers and leaves when they fall off the plants?
Refer to a student question (if one has been asked) as a jumping off point for the following investigation about decomposers or what happens to the leaves that fall to the ground.
If students haven’t asked this question themselves, add it to the list of class questions and discuss that answering this question will be the centre of today’s investigation.
The Inquire phase allows students to cycle progressively and with increasing complexity through the key science ideas related to the core concepts. Each Inquire cycle is divided into three teaching and learning routines that allow students to systematically build their knowledge and skills in science and incorporate this into their current understanding of the world.
When designing a teaching sequence, it is important to consider the knowledge and skills that students will need in the final Act phase. Consider what the students already know and identify the steps that need to be taken to reach the level required. How could you facilitate students’ understanding at each step? What investigations could be designed to build the skills at each step?
Read more about using the LIA FrameworkThe Investigate routine provides students with an opportunity to explore the key ideas of science, to plan and conduct an investigation, and to gather and record data. The investigations are designed to systematically develop content knowledge and skills through increasingly complex processes of structured inquiry, guided inquiry and open inquiry approaches. Students are encouraged to process data to identify trends and patterns and link them to the real-world context of the teaching sequence.
When designing a teaching sequence, consider the diagnostic assessment (Launch phase) that identified the alternative conceptions that students held. Are there activities that challenge these ideas and provide openings for discussion? What content knowledge and skills do students need to be able to complete the final (Act phase) task? How could you systematically build these through the investigation routines? Are there opportunities to build students’ understanding and skills in the science inquiry processes through the successive investigations?
Read more about using the LIA FrameworkDecomposing fruit
Show the video Fruit and vegetable decomposition, Time-lapse (1:36 min).
After playing the video once, assign collaborative teams a specific fruit or vegetable from the bowl to observe. Discuss with students what they will look for as they make their observations, and how they might record them.
Play the video at least once more. You may wish to watch the video multiple times to support students observations.
Discuss what happens to things as they rot, calling on teams to share what they observed about specific fruits or vegetables as the need arises.
- What happened to the fruits and vegetables over time?
- They got smaller, shrink, rotted away.
- What made the fruit and vegetables ‘shrink’ (or other term offered by students)?
- Did they actually shrink?
- Does it change colour? What colour will it change to?
- Did anything 'grow' over some of the fruit?
- Show the video again to examine the peach decomposing (black fungi 0:13-0:17) and apples decomposing (brown fungi 0:27-1:36 minutes).
- Were there any insects hanging around the fruit in the video?
- Fruit flies were seen.
- What might attract the flies to the fruit?
- The smell and chance to eat some of the decaying fruit.
- How long does it take for the fruit or vegetable to become unrecognisable?
- Does your fruit or vegetable have a thick or thin skin?
- Does that make a difference to how long it took to start being affected?
- Thicker, multi layered outer surfaces are usually more protected from external fungi or bacteria.
Introduce the term decomposer: a living thing/consumer that gains its energy from dead or decaying things. Add it to the word wall.
Students cut out the pictures on Decaying fruit Resource sheet and, in consultation with their collaborative teams, place them in the correct order of healthy to decomposed. They add the ordered images to their science journals.
Decomposers and detritivores
Decomposers are organisms (living things) that gain their energy from the chemical energy left in other organisms that have died.
A decomposer is an organism (living thing) that gain their energy from the chemical energy left in dead organisms. Fungi (such as mushrooms and mould) and bacteria (single-celled organisms) are examples of these food chain consumers. They release chemicals onto the surface of decaying plants and animals, breaking down the large chemicals into smaller nutrients that can then be absorbed.
Detritivores (de-tri-ti-vores) are different to decomposers because they need to ‘eat’ the decaying matter and break it down internally before absorbing the nutrients. Worms, millipedes, woodlice, dung beetles and slugs are all detritivores.
Decomposers and detritivores are linked to each part of the food chain as all organisms eventually die.
A decomposer is an organism (living thing) that gain their energy from the chemical energy left in dead organisms. Fungi (such as mushrooms and mould) and bacteria (single-celled organisms) are examples of these food chain consumers. They release chemicals onto the surface of decaying plants and animals, breaking down the large chemicals into smaller nutrients that can then be absorbed.
Detritivores (de-tri-ti-vores) are different to decomposers because they need to ‘eat’ the decaying matter and break it down internally before absorbing the nutrients. Worms, millipedes, woodlice, dung beetles and slugs are all detritivores.
Decomposers and detritivores are linked to each part of the food chain as all organisms eventually die.
The Inquire phase allows students to cycle progressively and with increasing complexity through the key science ideas related to the core concepts. Each Inquire cycle is divided into three teaching and learning routines that allow students to systematically build their knowledge and skills in science and incorporate this into their current understanding of the world.
When designing a teaching sequence, it is important to consider the knowledge and skills that students will need in the final Act phase. Consider what the students already know and identify the steps that need to be taken to reach the level required. How could you facilitate students’ understanding at each step? What investigations could be designed to build the skills at each step?
Read more about using the LIA FrameworkThe Investigate routine provides students with an opportunity to explore the key ideas of science, to plan and conduct an investigation, and to gather and record data. The investigations are designed to systematically develop content knowledge and skills through increasingly complex processes of structured inquiry, guided inquiry and open inquiry approaches. Students are encouraged to process data to identify trends and patterns and link them to the real-world context of the teaching sequence.
When designing a teaching sequence, consider the diagnostic assessment (Launch phase) that identified the alternative conceptions that students held. Are there activities that challenge these ideas and provide openings for discussion? What content knowledge and skills do students need to be able to complete the final (Act phase) task? How could you systematically build these through the investigation routines? Are there opportunities to build students’ understanding and skills in the science inquiry processes through the successive investigations?
Read more about using the LIA FrameworkGallery walk
Conduct a gallery walk to compare the similarities and differences between each decomposing fruit.
- How did you know which version of the fruit was most decomposed?
- On which fruit could you see the decomposer?
- What evidence do you have that the decomposer was present?
- What effect did it have on the fruit?
Students describe the effect the decomposers had on the fruit under the images in their science journal.
Discuss with students what living things leave behind, and what happens to those 'waste products'.
- What do plants and animals leave behind them as 'waste products'?
- Plants drop leaves and animals release poo/faeces.
- How many leaves do you think fall to the ground from some trees?
- Have you ever seen possums in the trees?
- Where do you think their poo goes?
- What do you think happens to all the leaves and poo on the ground?
- It eventually rots and returns to the soil.
- What helps to make this happen?
- Mould grows on it and rots it. Students might also offer the idea that small animals feed on the leaves and droppings. This will be explored further in subsequent lesson steps.
The Inquire phase allows students to cycle progressively and with increasing complexity through the key science ideas related to the core concepts. Each Inquire cycle is divided into three teaching and learning routines that allow students to systematically build their knowledge and skills in science and incorporate this into their current understanding of the world.
When designing a teaching sequence, it is important to consider the knowledge and skills that students will need in the final Act phase. Consider what the students already know and identify the steps that need to be taken to reach the level required. How could you facilitate students’ understanding at each step? What investigations could be designed to build the skills at each step?
Read more about using the LIA FrameworkIdentifying and constructing questions is the creative driver of the inquiry process. It allows students to explore what they know and how they know it. During the Inquire phase of the LIA Framework, the Question routine allows for past activities to be reviewed and to set the scene for the investigation that students will undertake. The use of effective questioning techniques can influence students’ view and interpretation of upcoming content, open them to exploration and link to their current interests and science capital.
When designing a teaching sequence, it is important to spend some time considering the mindset of students at the start of each Inquire phase. What do you want students to be thinking about, what do they already know and what is the best way for them to approach the task? What might tap into their curiosity?
Read more about using the LIA FrameworkIntroducing detritivores
Pose the question: Do you think there are decomposers in our bushland/garden/park/compost bin? All environments will contain detritivores of some description.
Introduce the term detritivore: larger animals such as worms, dung beetles, slaters and slugs that do a similar job as decomposers. Detritivores eat the decaying leaves, animals and poo to take the chemical energy stored in them.
Add ‘detritivore’ to the word wall.
The Inquire phase allows students to cycle progressively and with increasing complexity through the key science ideas related to the core concepts. Each Inquire cycle is divided into three teaching and learning routines that allow students to systematically build their knowledge and skills in science and incorporate this into their current understanding of the world.
When designing a teaching sequence, it is important to consider the knowledge and skills that students will need in the final Act phase. Consider what the students already know and identify the steps that need to be taken to reach the level required. How could you facilitate students’ understanding at each step? What investigations could be designed to build the skills at each step?
Read more about using the LIA FrameworkThe Investigate routine provides students with an opportunity to explore the key ideas of science, to plan and conduct an investigation, and to gather and record data. The investigations are designed to systematically develop content knowledge and skills through increasingly complex processes of structured inquiry, guided inquiry and open inquiry approaches. Students are encouraged to process data to identify trends and patterns and link them to the real-world context of the teaching sequence.
When designing a teaching sequence, consider the diagnostic assessment (Launch phase) that identified the alternative conceptions that students held. Are there activities that challenge these ideas and provide openings for discussion? What content knowledge and skills do students need to be able to complete the final (Act phase) task? How could you systematically build these through the investigation routines? Are there opportunities to build students’ understanding and skills in the science inquiry processes through the successive investigations?
Read more about using the LIA FrameworkKeeping it local
Discuss how students could test if there were decomposers or detritivores in their local environment.
- Will we be able to see the decomposer?
- We may see fungi, or it may be too small to see.
- Will we be able to see the detritivore?
- Probably, if we're careful and quiet.
- What evidence could we use to see if it is present?
- How could we test if a decomposer is there?
Students consider which of the below tests would be most appropriate for their environment.
If the habitat is controlled, students may choose to place the piece of cut fruit on the ground and place the clear plastic container over the top. They could take pictures of how it changes or write descriptions over time.
If there is a chance the location could be disturbed, use gloves and the trowel to collect a small amount of soil and humus (the dark organic material including leaves and bark) and place in the sealable container. This should also include decomposers. Add the cut fruit on top and seal the container tightly.
Store the container in a warm place in the classroom. Take pictures of how it changes or write descriptions over time. Do not reopen the jar as fungi can produce spores that can affect those with compromised immune systems.
Set up the experiment in the decided location. Encourage students to identify any detritivores that may be in the habitat.
- Where are these animals located? Are they close to the top or deeper down?
- How many different types of detritivores can you find?
- Should we touch these animals? Why not?
- No. They are important to the environment, and we need them to do their job.
- How are these animals different to decomposers?
- They are animals that can be seen. They need to eat the dead thing to get their energy.
- How are they the same as decomposers?
- The are usually too small to be seen. Both are consumers that get their energy by breaking down the chemicals in dead things.
The Inquire phase allows students to cycle progressively and with increasing complexity through the key science ideas related to the core concepts. Each Inquire cycle is divided into three teaching and learning routines that allow students to systematically build their knowledge and skills in science and incorporate this into their current understanding of the world.
When designing a teaching sequence, it is important to consider the knowledge and skills that students will need in the final Act phase. Consider what the students already know and identify the steps that need to be taken to reach the level required. How could you facilitate students’ understanding at each step? What investigations could be designed to build the skills at each step?
Read more about using the LIA FrameworkFollowing an investigation, the Integrate routine provides time and space for data to be evaluated and insights to be synthesized. It reveals new insights, consolidates and refines representations, generalises context and broadens students’ perspectives. It allows student thinking to become visible and opens formative feedback opportunities. It may also lead to further questions being asked, allowing the Inquire phase to start again.
When designing a teaching sequence, consider the diagnostic assessment that was undertaken during the Launch phase. Consider if alternative conceptions could be used as a jumping off point to discussions. How could students represent their learning in a way that would support formative feedback opportunities? Could small summative assessment occur at different stages in the teaching sequence?
Read more about using the LIA FrameworkDecomposers in the food chain
Revisit the local environment food chain from Lesson 5. Discuss where decomposers fit into a food chain.
- Are decomposers producers or consumers?
- Consumers.
- What do decomposers eat?
- Everything in the food chain.
- Where do they get their energy from?
- The chemical energy stored in the body of other organisms.
- How could we show this movement of energy in a food chain?
- How could we use what we know in the local bushland/school garden/compost bin?
Reflect on the lesson
You might:
- update the word wall with relevant words and images.
- update the TWLH chart by inviting students to add what they have learned (L) and the evidence/observations that show how (H) they now know that.