Skill A-Analysing Evidence and Drawing Conclusions

To get a mark of 2:

• You should make a simple, relevant statement of what you have found out. Your explanation should be consistent with your results, and probably based on your everyday experiences. (You should not just re-state your results!)

To go on and get a mark of 4:

• You need to process your information, so that it can be presented in the form of a diagram, chart or graph. (This can be in the form of a flow chart to show how something has changed, or a bar chart, pie diagram or line graph.)
• You should draw attention to any patterns or trends in your results.

To improve on this and get a mark of 6?

• You must choose an appropriate way of representing your results. This may be as a histogram, or as a line graph with a line/curve of ‘best fit’. (Graphs should be plotted accurately, using a sharp pencil. A line of best fit should be drawn as carefully as possible, not a dot to dot line. You need to make sure that the graph is fully labelled. Some computer packages will draw graphs, but will not draw a line of best fit, so you may need to draw this on by hand. )
• You should try to use numerical calculations to process your results. (eg. This could involve using distances and times to calculate speed.)
• You need to draw a conclusion that is consistent with your evidence, and this requires detailed discussion related to your scientific knowledge and understanding, using scientific terminology. (You should try to use information from your graph to pick out patterns, eg. Compare the speeds of the trolley if the height of the ramp is varied – if the height is doubled, is the speed doubled? Quote the data, then try to explain the pattern in terms of the science involved. This may mean repeating explanations from your plan, but you may find that it has a different slant in the light of your practical work.)

What else would be needed to get a mark of 8?

• On top of what you need to do for 6 marks, you need to deal with more complex investigations, often involving many variables.
• You need to choose the most appropriate way of processing the data. (Perhaps using mathematical calculations to process evidence for your conclusion, in addition to graphs, eg. Working out rates of a reaction under different conditions. You could even come up with a mathematical relationship.)
• You need to draw a logical conclusion from the evidence, showing how your conclusions can be related to the relevant scientific knowledge. (You must discuss the scientific ideas, even if this means repeating explanations from your plan – you may find that it has a different slant in the light of your practical work. If your results do not fit the prediction, you will be able to suggest new explanations, and you can gain credit for explaining why things did not turn out as expected.)
• You can even use the data to make further predictions.
• You can go on to use data from other sources and use it to compare with your own results and conclusions. (eg. from a different experimental technique or secondary sources, such as books.)