Repeated tests for reliability
CONCEPTUALDistinguish between precision (consistency of repeated readings) and accuracy (closeness to true value), use significant figures and standard form correctly, and choose and use appropriate measuring instruments to minimise uncertainty
Mastery Evidence
- Explains the distinction between precision and accuracy with examples
- Rounds measurements to an appropriate number of significant figures
- Selects a measuring instrument with appropriate resolution for the context (e.g. choosing a 10 ml measuring cylinder rather than a 1-litre measuring jug for a 5 ml measurement)
Assessment Prompt
“If [child] weighed the same stone five times and got very similar answers but they were all slightly too high, could they explain the difference between being precise and being accurate — and why having lots of repeats doesn’t always fix the problem?”
Curriculum Standards3 alignments
KS3.Sci.WS.SA.5The national curriculum in Englandcarry out experiments appropriately having identified potential risks
KS3.Sci.WS.VUSN.1The national curriculum in Englanddevelop their use of scientific vocabulary and nomenclature
KS3.Sci.WS.VUSN.2The national curriculum in Englandrecognise the importance of scientific quantities and understand how to use them
Prerequisites1
- Accurate MeasurementhardAges 9—11
Show full prerequisite tree
- Accurate Measurement hard
Precision vs accuracy and significant figures build on KS2 experience of taking careful measurements with repeat readings
- Measuring accurately hard
Must take measurements before increasing accuracy/precision with repeat readings
- Measurable Attributes of Objects soft
Systematic scientific measurement builds on understanding measurable attributes from maths
- Asking Questions soft
Formulating scientific questions builds on the general skill of asking relevant questions to extend understanding, developed in English speaking and listening
- Question Words hard
Generating effective questions requires knowledge of question words (who, what, where, when, why, how)
- Feeling of not understanding soft
Using talk to explore ideas and speculate requires noticing what you don't yet understand — the comprehension-monitoring habit in a spoken register
- Asking for Help hard
Noticing confusion and acting on it requires already knowing that asking for help is a valid response to being stuck
- Observation vs Interpretation soft
Asking good scientific questions requires noticing the distinction between observation and interpretation — a question like 'why did this happen?' only makes sense once you've separated what you saw from what you inferred
- Feeling of not understanding soft
Noticing the observation/interpretation distinction requires monitoring your own thinking — the universal comprehension-monitoring habit applied to scientific reasoning
- Asking for Help hard
Noticing confusion and acting on it requires already knowing that asking for help is a valid response to being stuck
- Feeling of not understanding soft
Asking scientific questions is the science-domain expression of the universal comprehension-monitoring habit: noticing what you don't yet understand
- Asking for Help hard
Noticing confusion and acting on it requires already knowing that asking for help is a valid response to being stuck
- Persisting When It's Hard soft
Scientific enquiry requires persistence through uncertainty — the universal persistence habit underpins willingness to keep investigating
Unlocks1
- Tables, charts, and graphssoftAges 12—13