Where I am, level 3 TAs do take whole classes on occasions. We cover first day teacher absence. After the first day a supply teacher is got in. And we cover PPA time for our own class, for me this is one hour a week. We also sometimes take our own phonics group - which can be 20+ children depending on the group. This is the same here for all the leevl 3 TAs. There is now ay they;d pay me teacher rate whilst the other TAs got normal TA rate, and I wouldn't expect it. However if I were to do more than that - such as second day cover, or cover the teacher on my day off I'd be sorely tempted to ask for supply teacher rate.
The difference in pay is massive yes. I get less than £10 an hour now. But for me at the moment the flexibility and the lack of stress and paperwork, and all the workload of a teacher, makes it worthwhile.
I do do work over and above what I am supposed to do, but partly that is just part of my nature - I like to have things very organised and I like to keep full records for example, so I sort this in my own time. I don't have to.
We are not supposed to plan for the lessons we take, but sometimes I do, esp for the lesson I do during my teacher's PPA time. It is the subject I used to teach, so I find it just as easy. The teacher would happily plan it for me though, and I do know which topics to cover through her too.
Have to say that I do love my job and everything from my class teacher, senior management, etc. is always 100% positive.
It was only the comments I heard yesterday that shook me, which came from a couple of the TAs.