Having been a Head of Maths for most of my teaching life, I'm now teaching Maths with a bit of Computer Science on supply. The 'bit of' is likely to turn into a 'lot of' soon, as I take over a Computer Science maternity cover. If I'm honest, I've never been happy with the teaching of Computer Science side of my career, although it has been the lesser part after maths. I've always found it very hard and challenging with classes where breaking problems down, algorithms and coding immediately turn off perhaps 5 out of 30 in a class, added to another 3 or 4 who are pains in all classes and disruptive. Trying to get students to listen, stay engaged, concentrate, read instructions, be self-reliant - all very hard work compared to maths. As far as the programming side of things go, I've tried using Codio and similar, using a book, using a free eBook and using a problem-solving approach - doing one or two problems each lesson. So, where am I going wrong? Is there a definitive text for teaching mixed ability students in secondary school I have missed? Who has the answers?