Surely it is a right to go to the toilet when one needs to? Obviously, if that right is abused then teachers should speak to pupils collectively about it or individually if certain students don't heed the warning.
I do think there is truth in some students not valuing education and I'm not quite sure how that should be addressed. There are so many distractions these days and there are so many expectations that life should be entertaining all the time. It is a very hard job these days being a teacher and I think that, given the challenges, most of them seem to do pretty well.
I think when I was at school, most children just sat and did what they were told without questioning anything. From what I recall, if they were bored in a lesson they just "tuned out" rather than become disruptive. (Though I did go briefly to one co-ed secondary school where an older male English teacher was finally reduced to tears as he tried to read a poem as paper aeroplanes were thrown round the classroom. I found the whole episode so distressing that I said I was going to leave school as soon as I could, but my parents got me into another school).
Although I feel every child should leave school with reasonably good literacy and numeracy skills, I think there is far too much emphasis on academic achievement now. Young people seem to do so many subjects these days that perhaps there is little time to concentrate on "soft skills" like introducing oneself with a smile and a firm handshake, being able to engage in conversation about a range of subjects, etc.