Am a student teacher preparing for teaching placement. I want to know whether is it important for veteran teachers to prepares session plan/lesson plan?

Moved here by me...

The short answer is yes, although most veterans will comfortably work from the weekly plan or, for certain subjects, the Medium Term plan.

All that will change around ofsted time, with teachers producing 'proper' lesson plans for the inspection.

Also, the national grid for learning sites will be really helpful to you in providing complete schemes of work for mathematics & literacy, and several other topic based lesson plans - on which you can base your own planning (or adopt outright if that's what the school uses).

You'll want to try and persuade your mentor to give you a copy of the medium term plan too... and agree your teaching commitments so you can plan effectively and with a scaffold.

Well put D I can only add..........make sure you do the planning when asked. Teachers don't mind if you don't get it quite right and they can show you how to improve it but they do mind if you go in without any as happened in our school once or twice.

.....and show differentiation and add a list of AfL questions