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Self Assessment

Here is an situation given to pupils which involves micro-organisms, decay and disease.

They are asked to explain what is happening.

What kind of explanations, language and words do you think pupils at various levels would give which reflect their understanding or misconceptions?

When you have done this, compare your thoughts with the actual pupil responses given below.

Alexander's mum finds some left over chicken in the fridge.

So, she makes chicken sandwiches for his packed lunch.

It is a lovely warm summer's day, and when Alexander gets to school he puts his lunch box on the window sill.

At lunch time he picks up a sandwich, smells it, and says "yuk! this chicken's gone off."

What do you think is going on inside the chicken to make it smelly and no good to eat?

Actual Year 6 pupil responses (look at these after completing Task 1)

Most pupils seem to appreciate that food goes off as a result of microbial action:

the majority of pupils (70%) said the chicken had bugs or germs in it, but showed a lack of differentiation between types of micro-organisms

just over half mentioned something or a substance in the chicken that goes bad when warmed

40% indicated that the chicken had been contaminated by the (warm) temperature itself

a few attributed the contamination to the "ink" in the lunch box. This was actually contrived to see if any pupils gave this response - and they did. It demonstrates that pictures can introduce unnecessary confusion.

two pupils said that the chicken had been deliberately poisoned in the shop by animal rights activists. There had been recent media coverage of this issue

"Germs lay in eggs in holes". (one pupil). Showing confusion between microbes and animals.

Ecosystems:

1	a diversity of organisms exists, and includes bacteria, fungi, plants and animals;

2	a diversity of organisms is found in most habitats; the organisms, including humans, in an ecosystem interact with each other and with the physical aspects of the environment;

3	micro-organisms are widely distributed.

to support the teaching of KS1 and KS2 Programmes of Study, for example:

locally occurring animals and plants can be identified and assigned to groups using keys;

food chains describe feeding relationships and generally start with green plants