Even when schools do have text books, they're barely used. It's all a confusing mixture of "scrappy home made worksheets", photocopies, notes/questions written by hand in exercise books from the white board or dictation, etc.
Likewise, I was very surprised that text books were barely used. When doing viewing at open days before he choose and at parents' evenings and other events, there seemed to be piles of textbooks everywhere. Son was even issued with his personal textbooks for some subjects. Yet, they still weren't used. Most of his text books looked brand new when he handed them back just like they were when he first got them. None of his homeworks were ever to read chapter x or do the questions on page yy - it was always to complete a worksheet, or go online and do a particular set of questions on xyz website.
Back in my day, you used a text book and it was like the bible/gospel for that year - we read from it in class, did the end of chapter questions for homework, teacher would work through it, etc. I hadn't realised all that had stopped. I found it much better that way as you had a single point of reference and more importantly, if you missed a lesson you could easily catch up yourself, just by reading the next chapter and doing the questions, in the hope that's what they were doing, which was usually right as teachers tended to follow the order of the text book.
Must be a mammoth waste of time for teachers to all be writing their own materials, creating their own worksheets, thinking up homeworks, finding online resources and putting details up on the school homework portal, etc.
Yes, I know text books go out of date. But surely most of the basics remain valid. I.e. pythagoras is still the same as it was 40 years ago. I remember back then we were using old O level textbooks for the new GCSE, but all that happened was the teacher would tell us to ignore, say, chapter 10 as it wasn't on the syllabus any more, or only go up to question 10 out of 20, because q's 10 to 20 were "too hard" for the new exam structure and wouldn't be examined, etc. All pretty simple "tweaking" really to use the same books for a slightly different syllabus. Same with the sciences - fundamentals are the same, i.e. gravity, equation for voltage, periodic table, components of the heart., so a generic text book of years ago is probably still 75% valid (or more) today.
I can't imagine such a fragmented way of teaching (i.e. lots of different resources, home made resources etc) is a "better" way of teaching. To my, it just causes confusion and complication if the pupil has to look at numerous different resources to find the information they need, especially at revision time. Would be far easier to just have a textbook or two.