I recently attended a weekend ASE event at the CELS centre at Nottingham Trent University. Hosted by the ever creative Mark Crowley we looked at the importance of practical work in science.
I would advise science teachers from all phases to check out the Getting Practical site which offers some ideas online and access to free CPD for science teachers.
There are many reasons why you might want to include practical activities in a lesson. Some of the reasons suggested include:
- To develop knowledge and understanding of science (e.g. show relationships between variables)
- Learn how to use apparatus and carry out scientific procedures (e.g. carrying out a titration)
- To learn the process of science enquiry (e.g. plan a strategy, interpret data and come to a conclusion)
The strategy recommends planning to include all of these intended learning outcomes in your schemes of work, and provides audit materials to assist you in this process.
The getting practical strategy is backed by SCORE (Science Community Partnership Supporting Education) and training is provided free of charge. With many schools currently rewriting their schemes of work it could be worth finding out more about Getting Practical.
Fiendishlyclever 
Have received “getting practical” training in northamptonshire. Has made me focus my practical work more and so they are less “flustery” – would recommend – you can organise as Inset (3 afterschool twilight sessions)