I think it is a load of bollox.. School is there to learn and to teach you how to learn. .
having a broad knowledge of things is relevant to life. . it can often show why were are where we are now and why decisions made now are made based on previous and historical experience and knowledge.It also makes people grow as they widen their knowledge in all things.
He mentions having a calculator so why does he need mental maths. Well sonny boy if you don't have a rough idea of the cost of what you've bought and what change you are going to get a calculator is a waste of time if you haven't input the correct numbers. The mental maths helps you know your input is correct and the calculator will just give you an more exact figure but, you should know roughly what it will be anyway.
Parents are meant to teach children the stuff related to the wider world. . why should schools be the ones taking over parenting roles. . Lazy parents makes for lazy kids who have a strop because they are being taught to learn and don't like what they are being taught. Tough! Get on with it, and parents start taking responsibility for your kids education in non academic subject. .it's YOUR job, not the teachers!
Fed up of moany kids having a strop because they 'don't want to do 'that' what ever that is'. Life is like that, you have to do stuff you don't want to do. . [your parents should have taught you that too] good luck getting a job, and keeping it, with an attitude like that 