There are new links at the bottom of this page to tell you about the new criteria for marking investigations. You will be marked under four sections: planning an experimental procedure, obtaining evidence, analysing evidence and concluding, and evaluation the evidence. Marks will also be awarded for spelling, punctuation and grammar. You are expected to use scientific and technical terms where appropriate.

How to set out you write-up: use the following sections. These links will take you to the appropriate part of this document. Just chose which one you want and click. You can jump about in the document; remember there is little point in looking at the section on the discussion until you have done the experiment.


  1. Front page // Title
  2. Aim
  3. Information
  4. Hypothesis
  5. Apparatus
  6. Plan
  7. Methods
  8. Results
  9. Discussion
  10. Appendices

If your account of the investigation uses the sub-headings given above, it will be much easier for the teacher marking your work to find the important bits which will earn your marks.

Front page // Title:

There are no marks for producing a fancy front page, so it will be a waste of time if you spend hours doing this. It just will not help you. When we mark your work we are looking for its content. Although you may not lose marks for poor spelling, when your work contains many spelling, punctuation and grammatical errors it gives a very bad impression, but a fancy front page does not make up for this. If you take more care over the front page that the quality of your writing, it makes you look rather silly.


This will only be a few sentences. You will be told at the beginning of the investigation what you are trying to find out. Therefore you only needed to write one or two sentences. This will get you as far as Level 1. We will know that you know what you are supposed to be doing. You may be given the aim of the experiment.


Before you start the investigation, you will already know something about the topic which you are given to investigate. The purpose of doing some research is to organise your existing knowledge so that you understand the Aim of the investigation. Downloading pages and pages from an electronic encyclopaedia is not a very useful thing to do: it does not prove that you understand anything. There are no marks for this section, but if you do not do any research your hypothesis will not be so good. If your work is copied from an encyclopaedia it is not possible for your teacher to know whether you understand the information, so you should write it in your own words.

You must do as much research as possible if you want to justify the predictions which you make and score level 8 for the planning section.

Here is an example: some students were asked to investigate the best conditions of fermentation.

They already knew that:

  1. yeast is a living organism,
  2. living organisms use enzymes,
  3. enzymes work faster if you raise the temperature,
  4. enzymes are denatured above 50 degrees C,
  5. enzymes work well at human body temperature,
  6. anaerobic respiration produces alcohol and carbon dioxide.

Their research might have shown them that:

  1. The higher the temperature is the faster the yeast ferments the sugar,
  2. There is a proportional relationship between the rate of fermentation and the temperature,
  3. If it takes a month to brew a gallon of beer, the yeast will not use all the sugar in 5 minutes,
  4. Heat makes the air in the tube expand, this produces some bubbles,
  5. Fermenting 1 gram of glucose produces about 270 mls of gas which is about 550 bubbles.

Their research might have involved:

  1. Reading their notebooks,
  2. Reading their textbooks,
  3. Reading encyclopaedias,
  4. Searching the Internet,
  5. Asking teachers specific questions.


You must write two thing in this section:

  1. Your predictions,
  2. An explanation.

In the prediction you say what you think will happen in your experiment. You should try to use your scientific knowledge in the hypothesis section. Give a prediction and explain it using your scientific knowledge. For example: if you are going to measure lots of temperatures, explain why you are going to do this.

You must decide how many measurements you are going to make. Here are some examples.

“I only want level 2 because I am very lazy I am only going to make 2 measurements.”

“I want to get a better level than that so I will make four measurements”

“I want very accurate results so I am going to repeat my experiment three times and take an average. Each time I do the experiment I am going to measure the rate of the reaction at 8 different temperatures so that I can demonstrate a proportional relationship between these two factors. I will also measure the factors which I hope to keep constant so that I can prove they did not change and affect the experiment.”

You will not lose marks by repeating things which you have already written in the Information section. You teacher will want to know that you have understood the information, so just copying the work from a book will not be good enough.


Your teacher needs to know what apparatus you will need. You will waste time in the practical lesson if you have not written this section. You must chose what apparatus to use if you want level 4 or better.


This section says what you will do. You will be writing in the future tense e.g. “I will measure out 10ml of glucose solution using a measuring cylinder”. You must write it before you do the experiments. If you do not do this you will waste time in the practical lesson. Try to ensure that your experiment will be a fair test. If it is not, you will not get Level 4. There is a new page on planning your experiment.


This section says what you have done. You will have written in the past tense e.g. “I measured out 10ml of glucose with a measuring cylinder”. You must write this after you have done the experiment. You will not lose marks because you did not do the experiment exactly as you planned it. While you are doing the experiment you may realise that there is a better way of doing something. You must try to make your experiment a fair one and you must make lots of measurements. Try to repeat your experiment. You have to make sure that your measurements are as accurate as possible. It helps if you repeat your experiment.

Have a look at the new page on obtaining evidence to find out what you need to do in your experiment to score good marks.


You must write down everything that you measured. When my students did their yeast experiment last year they had some difficulty keeping the water bath at a constant temperature. If they checked the temperature every 30 seconds they should have written this down. When I marked their reports I looked for evidence that they had tried to control the temperature. Those people who said that they had tried to control temperature got a higher level even if they said that it was difficult and it did not work very well. When I was marking their work I looked for the word “fair”.

You must write down everything that you measured. If you do not record your measurements the teacher who marks your work will assume that you did not follow this part of your method.

If you wish to include the results that other students obtained you must make this very clear. You must also comment on whether their experiment was a fair one: this is difficult to do if you have not watched them, helped them or read their methods. You must make it clear that you have actually made your own measurements: if someone helped you with your experiment, you must write down what they did. Perhaps you should have another look at the section on obtaining evidence.


This is probably the most difficult section to write. If you do not read this bit you are not likely to get a very high level. This section is marked on two sets of criteria. Firstly we have to look at the analysis of your results and the conclusions which you have drawn from them. Secondly we have to look at your evaluation of the investigation. Here are the kinds of things you might write about:

  1. Reference to the original prediction,
  2. Reference to fairness,
  3. Reference to safety,
  4. Descriptions of what happened,
  5. Explanations of what happened,
  6. Alternative explanations of what happened,
  7. Reasons for the things you did,
  8. Significance of the results,
  9. Suggestions for improvements,
  10. Suggestions for new experiments.

You could divide the discussion into three sub-sections:

  1. Analysis of Results,
  2. Conclusions,
  3. Evaluation.

Make sure that you have read and understood my pages on analysing the evidence and evaluating your experiment.


It helps whoever reads your work if you include the original results page (on which you recorded details of the experiment while you were doing it) at the end of you account. You don’t have to do this, but it does provide further evidence that you actually did the experiments.

Criteria for Marking Investigations.

This page has now been re-written to account for the new requirements of the London syllabus. There are now four strands instead of just three. Marks are also awarded for the quality of your writing. The skill areas are:

  1. Planning Experimental Procedures first draft now available. Max 8 Marks
  2. Obtaining Evidence first draft now available.Max 8 Marks
  3. Analysing Evidence and Concluding first draft now available.Max 8 Marks
  4. Evaluating Evidence first draft now available. Max 6 Marks
  5. Spelling, Punctuation and Grammar first draft now available. Max 3 Marks