My last blog post focussed on putting together a scheme of work – and I am sure that future blog posts will expand on this but I thought it was worth giving some ideas on Design labs.
A good design lab will allow your students to design a whole range or different and varied experiments and moderators love to see evidence of this. Whilst this sounds great, I do appreciate that the reality is a little different!
Before you give your class the design, there are a number of factors to bear in mind.
Firstly, is your question sufficiently open ended to allow students to design a whole range of different labs independent of each other?
‘Design an experiment to investigate the enthalpy of combustion of alcohols’ is really too narrow, yet something along the lines of ‘Investigate enthalpies of combustion’ is much more open ended.
The first research question is quite predictable in terms of the outcome but (and maybe this is why it is used) it makes life easier for the teacher and lab tech as it is much easier to manage in class. The second research question is much more open ended and hence much harder to predict what the students are going to do and hence much harder to manage in class.
Which brings me onto my next point – it is perfectly acceptable for students to only design labs and not to actually carry them out. Now this is interesting for a number of reasons.
Firstly, you don’t have to worry about ordering lots of different, expensive reagents and you won’t have to fall out with your lab tech when you ask for the department’s entire supply of organic reagents.
Secondly, there is no need to worry about the safety element of things … although the labs that the students design should be safe and in theory, they should be possible to do in your school lab. They need to be realistic. Using an NMR spectrometer is therefore not a realistic option!
Thirdly, student designed are sometimes not very good! This means that if you were also intending to use the lab for DCP and CE you may find that problems in the design lead to problems collecting the data, which ultimately means that the student will not get a great mark for D and DCP. It is far more productive to assess DCP and CE separately to Design and, if you do this, it means you are able to give a method that works!
So, finally, some ideas for you:
· Investigate intermolecular forces
· Investigate solubility
· Investigate heats of neutralisation
· Investigate an aspect of a redox cell
· Investigate electrolysis.
Yes, they are short and not very direct but will allow some good and imaginative labs to be designed by your students.
Good luck! I would love to hear about your experiences below.