The Scientific Process

Science is not only a set of facts to learn. Science is also something you do. The NSW syllabus says that the practice of science involves using the Working Scientifically processes. These are the skills and steps scientists use to find things out in a careful, organised way.

Working Scientifically means you do not just trust a hunch. Instead you ask a question, gather evidence, and check your thinking. A scientist who wants to know which paper towel soaks up the most water does not simply pick a favourite. They plan a test, measure carefully, and let the evidence decide.

The Working Scientifically processes include things like:

• Questioning and predicting: asking a question and making a sensible guess called a hypothesis.
• Planning and conducting: designing a fair test and carrying it out safely.
• Processing and analysing: recording data, then looking for patterns in it.
• Communicating: sharing your results clearly so others can check them.

You will meet each of these as we walk through a scientific investigation step by step.

A scientific investigation follows a clear path. Each step leads to the next, like rungs on a ladder. Here is the path, using the question "Does temperature change how fast sugar dissolves?" as an example.

• Question: ask something you can actually test. Example: does sugar dissolve faster in hot water than in cold water?
• Hypothesis: make a sensible prediction. Example: I predict sugar dissolves faster in hot water.
• Plan: decide what you will change, what you will keep the same, and what you will measure.
• Method: write the exact steps so someone else could repeat your test.
• Observe and measure: carry out the test and watch carefully, using a timer and measuring cups.
• Record: write down your results in a neat table as you go, not from memory afterwards.
• Analyse: look at your results and find the pattern. Example: the warmer the water, the faster the sugar dissolved.
• Conclude: answer your question using the evidence. Example: sugar dissolves faster in hotter water.
• Communicate: share your results so others can check or repeat them.

You do not always have to use every step, and sometimes a result sends you back to ask a brand new question. But this order gives you a reliable plan to follow.

An observation is something you notice using your senses or instruments. But there are two very different ways to observe.

• A casual observation is quick and loose. Example: "I reckon the plant near the window looks a bit taller." You did not measure, you did not write it down, and you cannot be sure.
• A systematic observation is planned, repeated and recorded carefully. Example: you measure each plant with a ruler at the same time every day, write the heights in a table, and do this for two weeks.

The word systematic means "following a system", a clear and organised plan. Systematic observations are stronger because they can be repeated and checked. If another student followed your exact steps, they should get a similar result. That is what makes the evidence trustworthy.

The NSW syllabus is clear that science uses systematic observations and controlled experiments, not casual guessing. So whenever you observe in science, slow down, measure, repeat and record.

A controlled experiment is a test where you change just one thing on purpose and keep everything else the same. This is also called a fair test. It lets you be sure that any change in your result was caused by the one thing you changed, and nothing else.

Think about the sugar question: does temperature change how fast sugar dissolves? To make it a fair test:

• Change one thing: the temperature of the water (for example cold, warm and hot).
• Keep these the same: the amount of water, the amount of sugar, the type of sugar, and how much you stir.
• Measure: how long the sugar takes to fully dissolve.

If you changed the temperature AND the amount of stirring at the same time, you could not tell which one caused the sugar to dissolve faster. By changing only one thing, you keep the test fair. You will look at this idea in much more detail in a later lesson, but the key idea to plant now is simple: change one thing, keep the rest the same.

You might wonder why scientists go to all this trouble. Why not just guess? Because a guess can be wrong, and you would have no way to know. A fair test gives you evidence, and evidence lets you trust your answer.

Here is what a good scientific process gives you:

• It is repeatable. If someone follows your method, they should get a similar result. That builds trust.
• It is fair. Because you changed only one thing, you know what caused the result.
• It removes lucky accidents. Repeating the test and recording carefully means one odd result does not fool you.
• It can be checked. Because you communicate your method and data, others can test it too.

Imagine telling your class "this paper towel is best, trust me." Now imagine saying "I tested all three brands with the same amount of water, three times each, and brand B soaked up the most every time." The second answer is far stronger, because it is built on systematic observations and a controlled experiment. That is the power of working scientifically.