It's important to discuss the value of practical work as science teachers, but we need to be aware of who is watching and what might be inferred.
Back in 2009/10 the target for our department from our 'mock-sted' was that there should be more practical work in lessons. We all knew it wasn't relevant as the previous one had been during the summer time when most classes were preparing for exams. I did a practical activity during my mock-sted lesson at the insistence of the HoF and it was rubbish as it didn't relate to the lesson at all. The students didn't see how it helped them and they were right. This sort of practical work we can do without. Practical work for the sake of it.
However, the pendulum has swung in a lot of places. There are senior management teams who see the share of the capitation that science departments get as unfair. There are those that observe lessons and see students collecting and returning practical equipment as a waste of time that they could have been redrafting an answer to an exam question. Practical lessons are too chaotic for a non-specialist to observe as being outstanding.
These departments are being pressurised in various ways (lesson observations, budget being cut, directly told) to stop doing practical work in favour of more written work, more mock exams and more delivery from PowerPoint (textbooks and worksheets cost money). These lessons look more ordered and are easier to show that progress has been made.
We have to make sure that in making the argument that a practical activity is not the only way to teach science, we are not saying that practical activities are not needed at all to teach science. And we need to be making the argument that schools have responsibility to fund the departments properly, give adequate technical support, have good schemes of work and ensure that services in classrooms are maintained. They should also give staff access to appropriate subject CPD.
Teachers should have the right to use their own professional judgement to use practical work if they so choose.