Planning a Practical Investigation and Risk Assessment

The plan is what gets marked

Task 1 is a practical investigation worth 20 per cent of the qualification, and you choose it from three titles set by CCEA. Here is the part students underestimate: the marks do not all sit at the end. The plan you write before you touch anything is itself assessed. Two tests decide whether a plan is any good. Could another person pick it up, carry it out safely, and get the same answer you did? And have you said WHY you chose each thing, rather than only what you chose?

Parts of an investigation plan

Six things a marker will look for in your plan.

Section to purpose

Could you actually do it?

The whole controlled assessment is meant to take around 45 hours, and you are working within a school year. Which of these investigations can realistically be planned and completed?

• Whether the depth grass seed is sown at affects how many seeds germinate
• Whether a four-year crop rotation improves soil quality on a field
• Whether a change of feed raises milk yield across a whole dairy herd
• Whether rising average temperatures have changed local grass growth

Say why, not just what

This is where most marks are quietly lost. A plan that says you will use fifty seeds per tray has stated something. A plan that says you will use fifty seeds per tray so that one seed failing does not distort the result has justified it. Every real choice in your plan has a reason behind it: why that equipment rather than another, why that many repeats, why you measure on that day. Write the reason down. A marker cannot award you credit for thinking you did not put on the page.

Which sentences justify?

Select the TWO sentences that justify a choice rather than only stating it.

• I will use three trays at each depth so that one odd tray does not decide the result
• I will set the depth with a ruler rather than by eye so that every tray is the same
• I will fill each tray with the same compost from the same bag
• I will count the seedlings in each tray after fourteen days

Writing the method

Begin by naming the one thing you will change, which is the _____ variable, and the thing you will measure, which is the _____ variable. List everything you will hold the same, because those are your _____. Then set out the steps in _____, in enough detail that another person could follow them without asking you anything. Say how many times you will repeat the whole thing, because a single run tells you almost _____.

The order of the plan

Put the stages of planning the investigation into the order you would actually do them.

• Choose your title from the three set by CCEA and decide what you want to find out
• Write a hypothesis, and name the variable you will change and the one you will measure
• Decide the technique and the equipment, and write down why each was chosen
• Write the procedure as numbered steps that another person could follow
• Complete the risk assessment and agree it with your teacher before starting
• Carry out the practical work and record what you observe as you go

Plan now, report later

Task 1 has two halves and they are marked for different things. Knowing which half you are writing stops you doing the wrong work at the wrong time.

A complete risk entry

These are four risk assessment entries from the example germination trial, which is used here only as an example and is not one of the CCEA-set titles. Select the ONE entry that is complete enough to let the work go ahead.

• Compost dust. Could irritate eyes and airways. I will fill trays slowly and wash my hands after.
• Compost can be dusty, so I will be careful when I am filling the trays up.
• There is a small risk from the glasshouse but nothing that should cause any real problem.
• Hand tools will be used during the practical work and stored away again afterwards.

What a risk entry needs

Looking at the entry that worked, what three things did it manage to say?

• The hazard, who or what could be harmed, and what will be done about it
• The hazard, the law that applies to it, and the penalty for ignoring it
• The hazard, the cost of the equipment, and where that equipment is stored
• The hazard, a promise to be careful, and a note that nothing serious will happen

A plan extract, marked

From the example germination trial, which is an example only and not a CCEA-set title. Hypothesis: grass seed sown at a depth of one centimetre will produce more seedlings than seed sown at three centimetres. Independent variable: sowing depth. Dependent variable: the number of seedlings counted after fourteen days. Controls: same seed from the same packet, fifty seeds per tray, same compost, same tray size, same watering, same position in the glasshouse. Technique and justification: depth set with a ruler rather than by eye, so that every tray is genuinely the same; three trays at each depth, so that one odd tray does not decide the result. Look at what earns credit there. Every control is named rather than summarised as keeping things fair, and both technique choices carry the word so, which is where the justification lives.

Records someone else could use

You are recording observations as the trial runs. Select the TWO things that make a record worth having afterwards.

• Writing measurements down at the time rather than from memory that evening
• Recording the date and the units alongside every measurement
• Copying the results out neatly at the end so the table looks presentable
• Leaving out any reading that looks odd so the pattern comes through clearly

Planning the germination trial

Work through the planning decisions for the example germination trial. It is used here as an example only and is not one of the CCEA-set titles.

• You want to find out whether sowing depth affects germination. What should your hypothesis do?
• You have two depths to compare. Which set of choices gives an honest comparison?
• Your teacher asks to see the risk assessment before you begin. Why does it come at this point?
• On day fourteen one tray has clearly been knocked over. What does the plan require you to do?

Write the plan for yours

Leave the example behind and write the plan for the investigation you are actually doing, or one you could realistically do in the time available. Nobody here can check your title or your setting, so what is being practised is the SHAPE of the plan: whether every section is present, and whether the choices carry reasons.

• State your hypothesis, worded so that a result could show it to be wrong
• Name the variable you will change and the one you will measure
• List the things you will keep the same, and say why each one matters
• Describe the technique and equipment, giving a reason for each choice
• Give one risk assessment entry with the hazard, who could be harmed, and your control measure
• Say how you will record your observations, and why that way is better than writing them up later