Year 6 classification: sorting plants, animals and micro-organisms

Classifying living things, explained

Classification means sorting living things into groups according to what they have in common. Scientists do it because there are millions of different organisms and sorting them makes patterns easier to see. In Year 6 children are expected to describe how living things are classified into broad groups using observable characteristics, based on similarities and differences, and to give reasons for putting plants and animals in a group. “Observable” is the important word: they look at features such as skin covering, legs, wings, how a young animal is born or what a plant produces.

The first big split is between animals with a backbone (vertebrates) and animals without (invertebrates). Vertebrates divide into five groups: fish (gills, fins and scales, living in water), amphibians (moist skin, with young that start life in water, such as tadpoles), reptiles (dry, scaly skin, and most lay eggs with tough, leathery shells on land), birds (feathers, wings, beaks and hard-shelled eggs) and mammals (hair or fur, feeding their young on milk, and mostly giving birth to live young). A handful of mammals, such as the platypus, lay eggs, but still feed their young on milk. Invertebrates include insects (six legs, three body sections and a pair of antennae), spiders (eight legs, two body sections, no antennae), snails and slugs (soft bodies, often with shells) and worms (long, soft, often segmented bodies with no legs).

Plants can be sorted too: into flowering plants, which make seeds inside flowers and fruits, and non-flowering plants such as ferns and mosses, which spread by spores, and conifers, which make their seeds in cones. Each broad group can be split again: flowering plants include grasses, trees and garden flowers. Micro-organisms are living things too small to see without a microscope. They include bacteria, some fungi (like yeast, which makes bread rise) and other tiny organisms. Many are harmless or helpful, such as those used to make yoghurt or cheese, and some cause disease. Fungi, such as mushrooms and moulds, are not plants, because they cannot make their own food from light, and they are not animals either. Scientists put them in a separate group of their own.

Children often use a classification key: a series of yes/no questions that leads to a single organism. “Does it have legs?” might lead to “Does it have more than six legs?” and so on. Children can make their own keys for local organisms, or use ones for pond animals or tree leaves, and research unfamiliar organisms they haven’t seen. Many schools mention Carl Linnaeus, the eighteenth-century Swedish scientist who developed the system of giving living things a two-part scientific name.

Words your child will hear

Classify

To sort living things into groups using shared features.

Vertebrate

An animal with a backbone: fish, amphibians, reptiles, birds and mammals.

Invertebrate

An animal without a backbone, such as an insect, spider, snail or worm.

Micro-organism

A living thing that is too small to see without a microscope, such as a bacterium or yeast.

Characteristic

A feature that helps to identify something, such as feathers or six legs.

Classification key

A set of questions with yes/no answers that helps you to identify an organism.

Amphibian

A vertebrate with moist skin that starts life in water, such as a frog or newt.

What the National Curriculum says

In Year 6, pupils should be taught to:

• Describe how living things are classified into broad groups according to common observable characteristics and based on similarities and differences, including micro-organisms, plants and animals
• Give reasons for classifying plants and animals based on specific characteristics

Objectives from the National Curriculum in England, © Crown copyright, used under the Open Government Licence v3.0.

A worked example

Common mistakes and how to help

How to help at home

• Sort the animals. Use toy animals or pictures of animals from magazines and library books. Ask your child to sort them into vertebrate groups and invertebrate groups, and to say which feature decided each one.
• Make a key. Choose six or so things from the garden or park, such as leaves or minibeasts. Write yes/no questions that split them up until each has its own route. Ask a family member to use the key to find an item you have picked.
• Minibeast hunt. Look under logs, in leaf litter and on walls (gently, with a magnifying glass, putting every creature and log back where it was and washing hands afterwards). Count the legs and body sections, and decide whether each find is an insect, spider, snail or worm.
• Awaken the yeast. Stir a pinch of dried yeast and a spoonful of sugar into a cup of warm (not hot) water and leave it for twenty minutes. The foam shows a living micro-organism feeding and producing gas. Don’t drink it.
• Odd one out. Choose three animals, such as a frog, a lizard and a goldfish, and ask which is the odd one out and why. There are often several correct answers, as long as the reasons are based on features.

Related topics

Everything in Year 6 science