Wednesday, June 22, 2011

Doing Experiments In High Schools Not As Effective As Thought?

This is an article from the UK questioning the effectiveness of doing experiments (or practicals, as they call it) in secondary schools in the UK.

Many standard school science practicals purport to be experiments when they are nothing of the sort. What we are doing a lot of the time, for example when asking them to "investigate the factors that affect the resistance of a wire", is getting students to carry out practical work with the intention that they discover something which is already known. This approach was described as "intellectually dishonest" by Rosalind Driver in her important essay, The Fallacy of Induction. It is naive and pedagogically unsound to think that all we need to do as science teachers is provide children the opportunity to discover the laws of science for themselves. As Driver wrote, "explanations do not spring clearly or uniquely from data". Yet this approach to practical work persists, according to Professor Robin Millar, due to "the prevalence of the empiricist/inductive view of science... the belief that ideas will 'emerge' automatically from the event itself, if students work carefully enough". As Millar, who has carried out extensive research into what students learn from practical work, points out, "in practice this rarely happens".

Whenever we see an argument like this, we need to separate out two distinct issues here:

1. Is the ineffectiveness is due to fallacy of the principle itself, i.e. the idea that doing experiments/practicals at this level is simply not contributing to the understanding of the subject matter, or

2. Is it due to HOW the principle is implemented, i.e. practicals can be useful IF it is done properly.

The article does not make that distinction, and in fact, has pieces from both.

My personal view on this is that, at THAT level (i.e. secondary school, high school in the US), lab work should be close to "playing" rather than trying to make the student discover known physics laws and ideas. In my series of essays on Revamping Undergraduate Laboratory, I basically listed the central philosophy of having such labs - making the student discovery the relationship between two or more variables, rather than making them discovery some physics concepts. In other words, I put the techniques of discovery, or how we know certain things, as being more important than trying to rediscovery Newton's laws.

Maybe that's something that can also be done to students at this level. But then again, when you have practicals at the A-levels testing you on stuff like this, one can't simply throw out the syllabus and do whatever one pleases.


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