Many Primary 6 Science questions distribute the evidence across several places. The text gives the conditions, the diagram shows the structure, the table provides measurements and the graph reveals the pattern. The pupil must combine these sources without mixing their roles.
This guide develops evidence synthesis across text, tables, graphs and diagrams for PSLE Science. It is different from learning to read any one representation: the focus is how to merge several evidence streams into one defensible scientific answer.
Return to the Primary 6 Science Learning Hub.
The synthesis rule
TEXT FOR CONDITIONS → DIAGRAM FOR STRUCTURE → TABLE FOR VALUES → GRAPH FOR PATTERN → SCIENCE FOR MECHANISM → ANSWER FOR THE REQUIRED JOB.
This is an eduKate reasoning routine, not an official SEAB formula.
Part I — Representations do different jobs
A paragraph may tell you what was kept the same.
A diagram may show which parts are connected.
A table may show exact measurements.
A graph may reveal a relationship over a range.
Do not ask one representation to do another’s job.
Part II — Read conditions before data
Data have meaning only inside their conditions.
If two plants have different bubble counts, first ask whether:
- time was the same;
- plant type was the same;
- water conditions were comparable;
- lamp distance was the intended change.
The table alone may not tell you these controls.
Part III — Use diagrams to define the system
A diagram can reveal:
- which object is the target;
- which path is complete;
- where a blockage occurs;
- which organism has alternative food;
- which part is upstream or downstream;
- which variable is measured.
Part IV — Use tables for exact comparisons
Tables are strongest for:
- specific values;
- repeated trials;
- averages;
- units;
- same-time comparisons;
- anomalous readings.
Do not rely on a graph when the question asks for an exact recorded value that the table provides directly.
Part V — Use graphs for patterns and boundaries
Graphs are strongest for:
- increase or decrease;
- rate of change;
- plateau;
- turning point;
- comparison across ranges;
- interpolation or cautious extrapolation.
Part VI — Build an evidence ledger
| Source | What it contributes |
|---|---|
| Text | Same plant, same water, lamp distance changed |
| Diagram | Lamp positions relative to plant |
| Table | Bubble counts at each distance |
| Graph | Overall decreasing pattern |
This separates evidence before synthesis.
Part VII — Synthesis is not copying everything
Choose the pieces that directly support the answer.
Question: Why does Plant C have fewer bubbles?
Relevant:
- C is farther from lamp;
- other conditions are comparable;
- C has lower bubble count;
- photosynthesis requires light energy.
Irrelevant details should stay out.
Part VIII — Resolve apparent conflicts
Sometimes text and graph seem inconsistent.
Example: text says “temperature was kept constant”, but a diagram labels different thermometer readings.
Do not ignore the conflict. Re-read the labels and determine whether the thermometers represent starting readings, later readings or different locations.
Part IX — Graph and table may use different summaries
A table may list individual trials while a graph plots averages.
If so, do not compare one raw trial directly with an average as though they were the same type of quantity.
Part X — Text may define an exception to the visual pattern
A diagram may look like two setups are identical, but text may say one container is insulated.
Always combine the written condition with the visual structure.
Part XI — Diagram arrows need contextual meaning
In a food web, arrows show feeding/energy relationships.
In a circuit, lines show electrical connection.
In a plant diagram, arrows may show transport direction.
Synthesis fails if arrow meaning is assumed incorrectly.
Part XII — Original case study: photosynthesis
Text: same aquatic plant, same water, five-minute count, different lamp distances.
Diagram: lamps at 10, 20 and 30 cm.
Table: 42, 31 and 20 bubbles.
Graph: decreasing output with distance.
Synthesis: As lamp distance increased, bubble count decreased under comparable conditions, consistent with less light reaching the plant and lower photosynthesis-related output.
Original case study: cooling cups
Text: equal water volumes, same starting temperature, different coverings.
Table: final temperatures after ten minutes.
Graph: cooling curves.
Synthesis: Cup Q remains warmer throughout most of the interval and has the smaller total temperature decrease, supporting the conclusion that Q reduces cooling more effectively under the tested conditions.
Original case study: branched circuit
Diagram: two lamp branches.
Text: one switch is opened.
Table: brightness before and after.
Synthesis: Only the branch containing the opened switch loses its complete path, while the other branch remains connected and its lamp can remain lit.
Original case study: food web
Diagram: Bird A eats X and Y; Hawk eats Bird A.
Table: X decreases, Y stable.
Text: no other environmental change stated.
Synthesis: Bird A retains Y as an alternative food source, so an immediate decline in Bird A—and therefore Hawk—is not certain.
Part XIII — Evidence priority
When sources differ in precision:
- use table for exact values;
- use graph for overall pattern;
- use diagram for structure;
- use text for experimental conditions.
This is not a hierarchy of truth; it is a hierarchy of fit to task.
Part XIV — Separate evidence from mechanism
Representations provide evidence.
Scientific knowledge provides mechanism.
Example:
Evidence: shorter car distance on Q.
Mechanism: greater frictional effect on Q.
Do not claim the graph itself “contains friction” unless friction is directly measured.
Part XV — Multi-source inference
Sometimes no single source proves the answer, but several together support it.
Example: text establishes controls, table shows consistent difference and diagram confirms the changed component. Together they support a stronger inference than any one source alone.
Part XVI — Cross-source contradiction check
Before answering, ask:
- Does the table agree with the graph?
- Does the diagram match the written condition?
- Are the units consistent?
- Are the same time intervals used?
- Does any source introduce an alternative explanation?
Part XVII — The MERGE test
- M — Map sources: what does each representation contribute?
- E — Extract: which facts are relevant?
- R — Reconcile: do sources agree?
- G — Ground: what scientific relationship explains the evidence?
- E — Express: answer the exact command.
This is an eduKate teaching mnemonic.
Part XVIII — Common synthesis errors
- Reading the graph without the experimental conditions.
- Copying every value instead of selecting evidence.
- Using a diagram’s appearance as quantitative evidence.
- Confusing a raw trial with an average.
- Ignoring conflicting labels.
- Using background Science to overwrite stated data.
- Explaining before identifying what the evidence actually shows.
Part XIX — Timed synthesis strategy
Under examination time:
- read command;
- mark conditions in text;
- trace structure in diagram;
- circle key values in table;
- read graph pattern;
- write one synthesis sentence;
- add mechanism only if required.
Where to connect
- Data, Graphs, Diagrams & Evidence
- Multi-Step Problem Solving, Constraints & Decision Paths
- Primary 4 Evidence Synthesis Across Text, Tables & Diagrams
Retrieval checklist
- I know what each representation is best used for.
- I read conditions before interpreting results.
- I use diagrams for structure and tables for exact values.
- I use graphs for patterns and boundaries.
- I select evidence instead of copying everything.
- I can reconcile text, tables and diagrams.
- I distinguish raw trials from averages.
- I separate evidence from scientific mechanism.
- I can detect contradictions across sources.
- I can combine several evidence streams into one concise answer.
The quiet return
Complex questions often become simple once each representation is given the right job. Evidence synthesis is the act of letting text define the world, diagrams reveal structure, numbers show measurements and graphs reveal patterns—then bringing them together without losing their boundaries.
Map the sources. Extract the relevant facts. Reconcile them. Ground them in Science. Express one coherent answer.
Return to the Primary 6 Science Learning Hub.
