Using investigations and demonstrations

Investigations and demonstrations give students an opportunity to explore science in a way that leads to them becoming questioning adults. They are both opportunities to introduce scientific enquiry and can be taught throughout the whole of the science curriculum to promote students� thinking and questioning skills. They should move away from the student only doing practical work as part of a full investigation and towards enquiry being an integral part of lessons.

Practical work, like any other aspect of teaching, needs careful planning. There is much evidence to show that the various forms of practical work open to a teacher to use can be highly motivational for students; however, motivation and providing �fun� activities are not sufficient justification for doing practical activity. The teacher, and therefore the students, should recognise the purpose of the activity, whether student-centred or led from the front in the form of a demonstration.

A short demonstration at the start of the lesson could:

• challenge the students to explain a phenomenon unfamiliar to them
• lead to further investigations which students themselves will conduct
• excite the students about a new topic they are about to encounter
• generate questions about the new topic.

Later on in the lesson, or at the end, a demonstration might help to summarise what the students have been learning during the session. In these cases, it is good practice to encourage students to link their learning with the observations they are making by attempting explanations of what is happening.