Children can recognise ‘fair tests’ before they are able
to produce these independently. When children are asked to undertake
pre-devised ‘investigations’, this recognition may take
the form of intuitive actions, carried out silently with no discussion
during any stage of the investigation.
• When presented with a prescribed task, children may perceive
little meaning beyond task completion in the actions they carry out.
Unless the context is familiar, children may struggle to recognise
variables that need to be controlled, or to develop a considered causal
theory that gives a sense of science meaning to their investigation.
• Year 8 children recognise and acknowledge more features of
fair tests than do Year 4 children. They are more likely to control
at least some variables, although they do not usually display any
other types of development in their approach to/understanding of fair
• Children find measuring laborious, and the context of a task
can greatly influence the measuring skills demanded of them (e.g.,
unfamiliar measuring tools distract from the main focus).
The act of measuring followed by written recording seems to partition
sequential tests into distinct episodes so that they are not immediately
seen as parts of a whole, coherent test design. Even when they have
planned a series of tests, children may deviate from their intended
plan part way through. Children’s more limited memory capacity
perhaps exacerbates this effect.
• Children typically ignore experimental error, apart from
occasional single instances of repetition when a result diverges
too widely from what they expected. However, they do understand
that even though individual results vary, main effects are robust.