3. Organising investigations
Thinking and behaving scientifically is most evident when pupils investigate something practically.
Investigating is a key skill in science. It involves you and your pupils in:
- deciding on the question you are trying to answer;
- deciding what equipment to use;
- deciding what measurements and observations to take;
- deciding how to present your results and how they give you an answer to the problem.
Case Study 3 shows how teachers can lead a class investigation of an ‘unknown’ substance. If the pupils have experienced a teacher-led investigation, they will be better prepared to do their own independent investigations of other substances. So we strongly advise you to attempt the case study lesson plan given in Resource 4: Planning an investigation with your pupils before trying the Key Activity.
In the Key Activity you will support groups in planning, conducting and reporting on their own investigations of ‘unknown’ white powders.
Case Study 3: A teacher-led pupil investigation
A few years ago, some colleagues were running in-service primary science workshops in rural Northern Ghana. In one series of workshops, a science lesson was planned, tested, reflected on and improved collectively.
The heart of the lesson was the teacher guiding the step-by-step investigation of the properties of an ‘unknown’ powder (powdered clay). First, the teacher focused on developing the skills of observation and communication in her pupils. Then she asked: ‘What will happen if we add a few drops of water to the powder?’ Pupils’ answers led to more investigation, observation and communication. On reflection, it was clear that the pupils were thinking and acting scientifically.
Read the detailed plan of the lesson in Resource 4. Here you will also find a suggested follow-up arts and crafts and language lesson.
Key Activity: Investigating unknown white powders
- Tell pupils that each group (three/four pupils) will be getting a different ‘unknown’ white powder to investigate. Remind them about properties and the steps and processes of the powdered clay lesson from the case study.
- Guide them as they plan the steps of their own investigation for the next day. They must include the equipment they need in their plan and perhaps some predictions. Give them time to share and improve their plans in class.
- The next day, hand each group a different ‘unknown’, BUT safe to use, white powder, such as icing sugar, salt, soap powder, sodium bicarbonate, fruit salts, maize meal, flour.
- Support them as they do their investigations and plan how to report on their findings.
- Can they identify the substances?
How did you assess their work? What advice would you give to a colleague who is going to do this activity?
A follow-up language lesson could be reading details on the packaging of substances used (see Resource 5: Reading packaging).
2. Exploring properties of materials