I have a feeling that logs used to be part of the GCSE (or O-level) at one time - is that right? If so - when did they get dropped? I checked the latest Singapore Maths spec and it's not even included there. I know they were included in the Additional Maths (which is now defunct isn't it? [unfortunately imho]) only a couple of years ago. I teach maths, physics and chemistry (to A-level) as a tutor - I would like to see logs included - certainly I find it helps when explaining the shape of the graph showing the change in pH during a titration and in radioactive decay.