How to answer 6 mark questions in GCSE science

Six mark questions are the longest answers on most GCSE science papers, and they are often the questions students dread most. They are also very learnable. Once you understand how they are marked and practise a simple planning routine, they can become some of the most reliable marks on the paper. This guide applies to biology, chemistry, physics and combined science on any board.

What six mark questions are

Six mark questions, sometimes called extended response questions, ask you to write a connected answer in full sentences. They test whether you can link ideas together, not just recall separate facts. Common types include:

• Describe a method, often for a required or core practical.
• Explain a process, such as how a vaccine works or how the structure of a material gives it its properties.
• Compare two things, such as two types of cell division or two ways of generating electricity.
• Evaluate a method, an argument or a set of data, and reach a conclusion.

How they are marked

Six mark questions are not usually marked one point per mark. Instead, examiners use a levels based mark scheme. Many science mark schemes use three levels, which broadly look like this:

The exact wording varies between boards and questions, so look at the mark schemes for your own board. The key message is the same everywhere: a short list of correct facts rarely gets beyond the middle level. To reach the top, ideas need to be developed and connected. Our guide to using mark schemes explains levels marking in more detail.

A five step routine

1. Read the question twiceUnderline the command word and the key topic words. A question that says explain needs reasons; one that says describe a method needs steps. Our guide to command words covers the difference.
2. Plan for one minuteJot down five or six key words or points in the margin. This stops you missing obvious ideas and helps you put them in order.
3. Order your pointsFor a method, chronological order. For a process, cause then effect. For a comparison, alternate between the two things. For an evaluation, for, against, then conclusion.
4. Write in full, linked sentencesUse linking words such as because, so, therefore and this means that. Use the correct scientific vocabulary.
5. Check against the questionReread the question. Have you answered every part? If it asked for a conclusion or a judgement, have you given one?

Aim for roughly six developed points. Writing much more than that rarely adds marks and costs time elsewhere on the paper.

Method questions

Questions that ask you to describe a method are among the most predictable, because they are usually based on the required or core practicals in your specification. A top level method lets someone else repeat your experiment and get valid results. Include:

• the equipment you would use, including measuring instruments
• the independent variable and how you would change it, with sensible values
• the dependent variable and how you would measure it
• the control variables and how you would keep them the same
• repeats, and what you would do with the results (such as calculating a mean)

An example

Question: Describe a method to investigate how the concentration of sugar solution affects the mass of pieces of potato. [6 marks]

A strong answer might read: "Use a cork borer to cut equal sized cylinders of potato and trim them to the same length. Blot each piece dry, then measure its mass on a balance. Place each piece in a separate boiling tube containing the same volume of sugar solution, using a range of concentrations such as 0.0, 0.2, 0.4, 0.6 and 0.8 mol/dm³. Leave all the tubes for the same time, for example 30 minutes, at room temperature. Remove each piece, blot it dry in the same way and measure its mass again. Calculate the percentage change in mass for each concentration. Repeat the experiment three times at each concentration and calculate a mean."

Notice that it gives the order of steps, names the equipment, states what is changed, measured and controlled, and deals with repeats and processing results.

Common mistakes

• Writing a list of keywords instead of linked sentences.
• Repeating the question back to the examiner before getting started.
• Describing when asked to explain, so the answer gives no reasons.
• Missing a part of the question, especially a final conclusion or judgement.
• Vague methods, such as "measure the potato" without saying what is measured or with what.
• Leaving it blank. Even a few relevant, accurate points can earn marks at the lower levels.

How to practise

• Collect the six mark questions from several past papers for your board and group them by type.
• Answer one or two a day under time, allowing about six to seven minutes each.
• Mark them against the level descriptions and the indicative content, then rewrite any answer below the top level.
• Learn the methods for every required or core practical on your specification. They come up often.

Find past papers for every board on our biology, chemistry and physics pages.

Frequently asked questions