Teaching Sequence

Work through this resource material in the following sequence:

15 minutes

Tune In: What do plants need?

15 minutes

Find Out: Consumers, producers and decomposers

25 minutes

Take Action: What green waste do we make?

05 minutes

Reflection

Tune In: What do plants need?

Step 1

Pose the question to your students:

What do plants need?

Keep a list of their ideas on the board or on butcher’s paper.

Once you have a list of ideas, ask your students:

What do you think happens when plants don’t get these things?

Step 2

Let’s take a look at some time-lapse videos that show what happens to a plant that is missing one of these key elements and what happens when it gets that element.

What’s a time-lapse? Imagine you have a camera that can take pictures. A time-lapse video is like a super-fast movie made from those pictures. Instead of watching things happen in real time, a time-lapse video makes everything appear much faster. It's like watching flowers bloom, clouds move, or construction happen really quickly, even though it actually took a longer time in real life. It's a fun way to see slow changes happen really fast!

Time-lapse 1: Water

Pause at the start of the video. Does the plant look happy? It has droopy leaves, brown patches, and looks like it could be dead. Let’s see what happens when we give it some water.

How did the plant look after it had been watered?

Time-lapse 2: Minerals

Watch the video to the 1:18 mark. Does this plant look healthy? Would you eat this basil? Skip forward to the 5:09 mark after iron has been added to the plant's water and watch the time-lapse. How did the plant look at the end? Did the leaves recover? How did the plant recover?

Time-lapse 3: Sunlight

Let’s take a look at what happens when the amount of light plants are getting is being controlled.

How did the changing light affect the growth of the plants?

What were the differences between the plants in changing light and the plants in regular light?

What happened to the plants on the very left and very right of the pot that were either in full light or full dark? (You may have to rewatch the timelapse to catch this one!)

Find Out: Consumers, producers and decomposers

Step 1

We’ve looked at three things plants need: sunlight, water, and nutrients.

Where do plants get sunlight from? (The sun!)

Where do plants get water from? (Rain/precipitation or groundwater)

Where do plants get nutrients from? (The soil)

But how do nutrients get into the soil? Let’s explore this further!

Step 2

What animals live under the ground? Keep a list of the different animals students suggest.

The word for an animal that spends the majority of its time underground is a ‘fossorial’. Some fossorials improve soil health by digging tunnels and holes and aerating the soil. Others are ‘decomposers’ who break down organic matter and put the nutrients and energy back into the soil.

Step 3

One very important decomposer is the worm. Let’s take a look at a video to see how worms do their job:

Wow! What busy little worms! What did they eat in this video?

paper
cardboard
leaves (fresh and dried)
grit (ground up eggshells for calcium)
ice (for moisture).

Step 4

Can worms decompose everything? Let’s make three lists:

things we know worms can decompose
things we know worms can’t decompose
things we’re not sure if worms can decompose or not.

From these lists, see if you can identify common properties to each list. Students will likely discover that things that worms can decompose were at one point alive (paper, food scraps, meat and other organics), and things that worms can’t decompose are non-alive (metal, plastic, glass, etc.).

Literacy extension: Have students practice writing questions they can enter into a search engine to find out if those items can be decomposed by worms or not.

Take Action: What green waste do we make?

Step 1

Ask students about what they have in their lunch box for today. What waste was generated from their lunch? Keep a list of these different items.

From this rubbish, which of these things could be put into green waste to break down and become good nutrient-rich soil for plants?

Some items, such as printer paper, can go into green waste, but recycling them is a better use of the resources and energy stored in them. If this is something your class wants to explore, they could look into the energy and resources required to make new paper versus the energy and resources required to make recycled paper.

Step 2

Now we know what our green waste is, what do we do with it? Ask students to suggest ways they have seen both at school and at home to turn this green waste back into soil for our plants. They might suggest:

worm farms
composting
green waste bins (if these are available in your LGA!).

You may have some households who use vegetable scraps for homemade stock, leftover fruit to make jam or feed their scraps to chickens, dogs, or other pets. If this is an extension you would like to follow, take a look at the Coles, Reducing Food Waste webpage and see if any of these methods are used in your students’ homes or could be implemented in your classroom.

Step 3

Let’s answer this question:

Where does our school’s green waste go after it has been processed?

This will vary based on what your school’s green waste system is. Some LGAs with a green waste collection system will have their green waste commercially composted for farmland rejuvenation. If you have a compost system at your school, you could take students outside to see where it is and where it is used.

If your school doesn’t have any green waste management, you could propose a hypothetical situation to students. If we DID have a compost system, what could we do with the compost? What plants at our school could use the good soil and rejuvenation?

You can watch this video to show students why having a school composting system would be useful.

Numeracy extension: Based on our sample of rubbish above, how much green waste do you think our class produces in a week? In a year? What about our year level? Or our whole school? Students can use familiar strategies to approximate the amounts of green waste.

Reflection

Ask students to complete the student worksheet by drawing 5 pictures in the circles.

What are four things that can go in the compost?

What is one thing that cannot go in the compost?

Plants and Compost: Let’s Break it Down

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