Describing trends, doing the calculations (mean, percentage change, density, magnification), explaining results, sources of error, limitations and conclusions.
5 narrated scenes. Press play, listen and read along — the points appear as they are explained. Use ‹ Prev / Next › or the scene bar to jump to any scene.
Your results are only half the story. The marks come from what you say about them.
Narration uses your device’s built-in voice. No sound? Switch to “Captions only” — the captions advance on their own.
Copy these into your notebook in your own words — that is how they stick.
General pattern + figures + any levelling off/anomaly.
Total ÷ number of values.
(final − initial) ÷ initial × 100.
Number counted ÷ area sampled (units: per m²).
Error = inaccuracy in measurement; limitation = weakness in design.
Answers the aim; supported by data; supports/refutes hypothesis.
Background, explanation/interpretation, conclusion, limitations (e.g. 2+3+2+1 = 8, scaled to 10).
The kind of support a teacher gives after the lesson: worked examples to attempt first, a board illustration, key terms, common misconceptions and memory aids.
Try it in your notebook first, then reveal the solution one step at a time.
Try it in your notebook first, then reveal the solution one step at a time.
Most A&I marks come from doing these four things in this order.
A&I in four moves: Describe, Explain, Evaluate, Conclude — “DEEC”.
When the Caribbean Public Health Agency (CARPHA) analyses disease data, it does the same things: describes trends, explains them, notes the limits of the data and draws conclusions for action.
Take any graph from a newspaper or website. Write one sentence for each of Describe, Explain, Evaluate and Conclude.
3 quick games on this lesson. Earn XP and badges as you play — your best score for each game is saved. Games are for practice and do not change your exam readiness.
6 items modelled on real CSEC Paper 1 questions. Choose one answer for each, then check. Aim for 80% or better.
Write full answers, then reveal the mark scheme and tick the points you earned (9 marks in total). Your answers are saved on this device.
Question 1 [9 marks]
Carrot strips (50 mm) were left for 1 hour in 0%, 5% and 10% salt solution. Final lengths: 53 mm, 49 mm, 45 mm.
(a) Describe the trend and calculate the % change in length for the 10% solution. [3]
(b) Explain the results. [3]
(c) State ONE source of error, ONE limitation and a conclusion. [3]
Everything in this lesson is based on these parts of the CXC syllabus and papers.