Food chains
Lesson Plan
Objectives
By the end of this unit the children should:
• Understand that plants are the producers in nearly all food chains as they convert energy from sunlight.
• Understand that when organisms die their energy and minerals return to the soil to be recycled.
• Know that a food chain represents the flow of energy from one organism to another and shows the
relationship between producers and consumers.
• Be able to identify primary consumers, secondary consumers, tertiary consumers and decomposers in a
food chain.
Key Teaching Points
Green plants are able to convert energy from sunlight into food stores by the process of photosynthesis.
Animals gain energy by consuming these plants or other animals that eat plants. This flow of energy from one
organism to the next is called a food chain. Each food chain shows the relationship between a producer, the
primary consumer that eats the producer, the secondary consumer that eats the primary consumer, and so on.
This flow of energy is represented by arrows. When any organism dies, decomposers break down and return
minerals and energy to the soil, to be recycled by other organisms.
Starter Activity (10 minutes)
Display the word search on the whiteboard. Ask the children’s help to find the hidden words.
Ask the children in pairs to discuss ways that the words in the word search could be linked. Ask for their
suggestions and give credit for each answer.
Display the Oak tree classroom visual on the whiteboard.
Ask:
1) What is different about this organism compared to all the others in the word search list? It is a plant, so it
produces its own food.
2) Where does the oak tree get its energy? From sunlight, which it converts to energy through photosynthesis.
Ask the children to suggest why the oak tree might be particularly important to the animals in the word search.
The oak tree is important to many of these animals as a source of food – for example, worms eat dead or
decomposing leaves, flowers and fruit; aphids eat flowers and fruit; caterpillars eat flowers and leaves; beetles
eat leaves and bark; squirrels eat fruit, nuts, leaves and bark. Other animals, like hawks and foxes, then feed on
the primary consumers.
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Food chains
Lesson Plan
Main Activity (40 minutes)
Play the film Food chain.
Organise the children into pairs or groups of four, and give each pair/group a Food
chains activity sheet and a sheet of paper.
Remind the children that most food chains begin with a plant that obtains its energy
from the Sun. In this case, the plant is an oak tree.
Write the following example of a food chain on the whiteboard: oak tree → caterpillar → sparrow. Explain to
the children that in this food chain the oak tree is the producer, the caterpillar is the primary consumer and the
sparrow is the secondary consumer. Ensure they appreciate that the arrows show the flow of energy along the
food chain.
Ask the children to look at the animals on the activity sheet and suggest how the food chain may be extended
further to introduce the idea of a tertiary consumer. Ask: Who eats the sparrow? Fox, owl and hawk.
Ask the pairs/groups to draw an oak tree on the left hand side of the sheet of paper, and use the animal
images to create a number of food chains that start with the oak tree. These should be recorded using
arrows to demonstrate the flow of energy through the food chain. In each case, the children should state
the producer, primary, secondary and tertiary consumers in the chain. Remind them that the activity
sheet provides a number of statements about what the different animals eat.
Point out that the food chains that the children have considered are all based around an oak tree, but that many
different types of plants act as producers.
Common misconception: Some children will think that an animal higher up in a food chain will eat all the
organisms below it. Ensure the children understand that the higher consumer only eats the organism that is
directly below it in the food chain.
Optional extra:
Write the following plants on the whiteboard: grass, wheat and cabbage.
Ask the children to work in pairs and create a food chain that develops from each of these plants.
Remind them to think of an animal (primary consumer) that eats the plant and so on. Point out that
insects and other small animals are important in many food chains. Write the following example on the
whiteboard: cabbage → slug → chicken → fox.
Play the film Sharks and fur seals.
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Food chains
Lesson Plan
Further Questions
•
When a plant or animal dies, what happens to the energy stored in it? Some will be eaten by animals. Those
that are not eaten are broken down by decomposers like bacteria, fungi and moulds. Decomposers absorb
some of their energy and release nutrients into the soils that can be absorbed by plants. Decomposers play a
vital role in ensuring that dead matter does not build up on the Earth.
Review (10 minutes)
Use one or more of the following films to conclude the lesson:
Play the film Jigsaw.
Ask the children to suggest a possible food chain involving the lion. For example, grass is eaten by an
antelope, zebra or warthog, which is then eaten by a lion.
Play the film Odd one out.
(You can pause at 00:30 and ask the children to share their answers with a partner.) Ensure the children
can explain the meaning of producer (something that can make its own food e.g. a plant) and consumer
(something that eats a plant or animal to gain energy), and the difference between a primary and
secondary consumer (a primary consumer eats plants; a secondary consumer eats animals that eat
plants).
Play the film What happens next?
(You can pause at 00:11 and ask the children to discuss with a partner.)
Play the film Did you know?
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