Computer Studies used to be offered at O-level (I did it). More recently ICT seems to be the only subject taught for GCSE at many schools. Looking at the exam boards' web site some are now offering a 'Computing' GCSE -- for example
FWIW: My kids' school does teach a bit of cookery.
I could understand that many schools would not be offering a course like Computing. I would guess that many teachers would not have the expertise to teach it. And those schools worrying about their position in the league tables might be put off (as it is probably more difficult than ICT).
At KS4, yes. At KS3, schools should have more freedom now there are no SATs. "Good" schools do often do more than teach just the syllabus too.
IME this is correct. There is so much bureaucracy in schools nowadays
- I'm surprised that teachers get any time to teach ;-)