Scientific reasoning is how you move from what an experiment shows to what you may safely say about it. Four small skills carry most of the weight, and this hub puts them in a sensible order.
What the four skills cover
- Distinguishing observations and inferences: what you saw versus what you conclude.
- Choosing an independent and dependent variable: what you change and what you measure.
- Reading a graph before drawing a conclusion: axes, units and shape first.
- Checking whether evidence supports a claim: does the data actually say this?
Why the order matters
Each skill feeds the next. You cannot name variables well if you have not separated what you observed from what you assumed. You cannot read a graph properly until you know which quantity is on which axis and why.
The last skill uses all three, so it makes a good test of whether the earlier ones are secure.
One experiment, four skills
A worked example: a student places identical paper cups of water at 20 °C, 40 °C and 60 °C and times how long a sugar cube takes to dissolve. The times are 95 s, 52 s and 28 s.
The observation is that the cube dissolved faster in warmer water. The variable being changed is temperature, and the one measured is dissolving time. A graph of time against temperature would slope downward.
The claim “heat makes sugar dissolve faster” is supported here, but only for this sugar and these cups. Claiming it holds for every substance goes beyond the evidence. You just used all four skills on one small table.
Who should start where
If you lose marks on “state what you observe” questions, begin with the first page. If your graphs are drawn correctly but your sentences underneath are weak, begin with the third.
If you are not sure, the prerequisite gap finder points to the right starting place. The wider foundation skills hub covers the Mathematics side of the same problem, and SPM Science tuition gives you a teacher to practise with.